desktop
XP 1280 x 1024
Linux 1024 x768
laptop
1024 x 768
I think 1024 x 768 is gonna be the new minimum, most people have a reasonably new PC with a TFT screen (all mine are) or a good quality crt monitor, and I haven`t seen a TFT lower than 1024 x 768 resolution and anyone with CRT is usualy using them because of their job/main hobby (video editing, hardcore gamer etc), so they have a good quality display, only kids with passed on computers from grandparents etc are gonna be on 800 x 600 imo (like the one I just refurbished for my workmates grandson
...Packard Bell executive multimedia 800 x 600 crt and 120mhz pentium, 32mb ram).
Mentor.
PC1:XP, P4 3ghz, 1gig mem, 3x160gig hd`s, Radeon 9800pro, 6 way speakers.
PC2: Linux, AMD 2ghz, 512mb ram, FX5200 ultra, 16 bit SB.
PC3: XP, laptop, intel 2.6ghz celeron, ATI mobility 9000, 256mb