Prepare for a LOT of reading, if you’re interested.
Massive Mover. I specifically made this to back-up my files and retain the original file dates because you can’t do the latter in Windows. I updated it today with new features, including crash prevention, error reporting, skipped-file reporting, progress-within-a-file reporting, and the ability to cancel while a large file is in the middle of transferring. It’s really not a very good idea to use Massive Mover to move files within a single drive, and it’s pointless anyway (because when moving files within one drive, Windows does retain the Created On date).
Color Counter. It even has its own small page! Simply designed to count colors in an image. Can load BMPs, GIFs, and PNGs, as well as some other formats that I don’t care about but Visual Basic programs can natively load them anyway. Color Counter’s basic functionality was later integrated into Kinesis Animator. I don’t even know why I posted this one. 
4Colors. Certainly not the best GUI ever–I didn’t even add a basic file “Browse” dialog–but it’s got some interesting graphic effects I haven’t seen elsewhere. Sine waves, Background Remover, Color Dominance (the color with the higher value shows in the final image–not necessarily the brighter one, sadly), and red/cyan 3D stereoscopic anaglyph. It was basically made for JPG images with a resolution that is a multiple of 4 in both width and height. So yeah, definitely not a very good program, but I’ve had fun with some of the effects. I even used one of them on my Rotis logo.
Anaglypher. I basically took the red/cyan 3D stereoscopic anaglyph effect and put it in a loop. Anaglypher is designed to turn two complete videos (of the same number of frames) into a single 3D anaglyph video, like SpyKids 3D. I’ve used it once, and I highly doubt anyone else will ever use it. But here’s an example clip. (Yes, it’s me, and yes, I’m acting dumb for the sake of the video! Also, the videos are misaligned, so you’d have to tilt your head to the right quite a bit to see the 3D effect if you had 3D glasses on.)
BinaryLoad. Quoted from my site: “Allows the user to edit small files as binary digits. This is mainly for lazy coders who want to see what bits they got wrong in their file-saving procedures.” I’m lazy, so I’m not even writing about it again. 
GenTile, the Metroid Genesis map editor. I think it’s awesome, and I think I programmed it really well ‘n’ stuff! It deserves much more text than I’m giving it. Here’s a sample map pack for it.
Tide. I love this program and use it all the time. It looks simple, very basic… But it has a built-in virtual keyboard, “super clipboard” (you can swap out the many slots with things in your clipboard), a sort of tab feature (not VISUAL tabs, but you can have lots of files opened in one window regardless), a keystroke emulator, an Always On Top option, and a very complex find/crop/replace/count (just replace with the same text) function, involving such features as “include X characters to the left/right” for replacing extra stuff, “not included within X characters to the left/right,” and multi-line functionality. (Man, I don’t know how many times I’ve wanted to replace newlines with commas and spaces!) It also asks you if you’re sure you want to save… That’s because I’ve overwritten files accidentally many times before.
Paint WIP Grabber. Also has its own page! Essentially takes a screenshot each time you release the mouse in MS Paint. Here’s a video I made using it–I’m sure several of you have seen that before.
MaskMaker. I made it to turn white into black and everything else into white. It’s sometimes useful if you need masks for a program you’re making (which you generally do when working with hardware accelerated graphics), or otherwise in combination with the next program on my list…
Glowem. Pretty much outlines (in a diamond fashion–not smart outlining) one color with any amount of colors up to 10. It’s kind of a poor GUI, since you have to type in your color values by hand, and you have to click on the pixel whose color you want to outline, without any help from a zoom. But I’ve used it plenty of times. Sample image.
Alphamaker. Here’s another program that was made by me, for me, and I don’t think I showed it to anyone else. It’s for making a 32-bit bitmap (which is pretty much entirely unsupported) out of one file for RGB and a separate file for the alpha channel. I made it for use with Meteroids (a game I made for Project Metroid), Rotis, and any other game I make in the future (ie. my current project, a top-down 2D mouse shooter) using my 2D OpenGL template.
BatMon. I have never even shown this one to anyone except in person, I believe. Its purpose is to give you a good graphical representation of how much power is left in your laptop’s battery. First, it’s blue, and after it empties you have about 2/3 of your battery life left, then it refills and turns yellow. It repeats with red the next time, and when your battery life is really low it gets cross-hatched. I was simply disappointed with Microsoft’s 4-image one and made my own. There are no options–and to close it, you simply left-click on its icon in your system tray.
MassRenamer. I pretty much made it so that when I rip a CD, I can copy and paste the songs’ names from elsewhere and quickly rename all the files. It’s also excellent for changing a large number of files’ extensions, if you use it in combination with the next program listed…
The Drag Drop File Lister. Designed to work with several of my programs, and possibly just for listing files.
Really Simple Slideshow. Also works well with The Drag Drop File Lister. This basically shows all the pictures listed (2 seconds each), resized to however large you set the window before clicking the “show slideshow” button. If you hit Delete, it’ll remove the currently visible entry from the slideshow file.
JoyMouse. I made it for fun, really. It lets you use any joystick or “game controller” (if it’s shown in the Game Controller app in the Control Panel) in place of a mouse–be it analog or D-pad. It’s got axis locks, a slow/accurate mode, left/middle/right-click, horizontal (but XP doesn’t natively support it…at least, not on purpose) and vertical scrolling.
ThumbLocker. This program blocks all mouse/keyboard input to your computer (except control-alt-delete) until you attach any drive, MP3 player, camera, CD, etc. that contains a specific file (included in the ZIP) in the root directory. For example, if you have a thumb drive known to your computer as drive K, you have the file K:\tacoA.ico, and your computer will only be usable if you have that thumb drive plugged in (as long as ThumbLocker is open). It doesn’t start on its own or anything, and it doesn’t care about the contents if tacoA.ico, so it’s not likely that your computer will be rendered entirely unusable even through careless use of the program.
Date2Date. That title may be self-explanatory. It’s simply a program that tells you how many days are between two given dates.
TypingTest. I really hope you see that one as self-explanatory.
Of course, I’m gonna plug my more prominent (or at least more posted-about) programs here as a side note, too:
Kinesis Animator (GIF animator designed for use with spritesheets)
Rotis (fun puzzle game basically similar to Bejeweled or Tetris Attack)
The DeMattei Project (equation grapher)
The Ultimate Board Game Engine (designed for users to create their own board games or recreate actual board games; features online play)
Rocket Soldier: Samus (older game in the style of the skateboarding/surfing levels on TMNT3 for NES)
Aaand here are other things I’ve posted that nobody commented on:
All my old games