International Galaxy S phones have a handy front-facing camera, but other Galaxy S users aren't quite as lucky. The phones are similar enough, though, that you can install one yourself.
This particular hack was originally done on a Samsung Vibrant (T-Mobile's Galaxy S phone), but it should work on other variations. It turns out that the camera chip is the same in all versions of the phone, and their cases even have a space where the missing front camera would go. Hacker Siirial over at the XDA Developers forums found that he could just snap a replacement camera right in, add some modded software and have a fully functional camera on the front of his phone.
The replacement camera only costs about $US16, and while the mod certainly isn't for the squeamish, it isn't too difficult — everything pretty much snaps right into place (no heavy tools or electrical skills required). Then, you just need to root your phone, flash a certain ROM, and throw a camera data file into the right folder to get it all working. Hit the link for the detailed how-to.