I thought this would be useful especially when considering forum design. I have a habit of catering to my resolution, but I'm not so sure most people use what I do, sooo...market research!
Two of our computers (including the one I use mainly) are set to 1024x768, and the third is at 1280x1024.
1280 x 800 - A widescreen laptop.
The other two computers in my house are both 1024 x 768, I believe.
1440x1024 on my laptop (widescreen) and 1280x1024 on my computer ^^. On school it's mostly 1024, but the screens such there, and I usually just bring my laptop along to school. So mainly it's 1280x1024 or larger.