[rab] Well, the buttons look better on my iBook screen! Something I will certainly need to remember next time I do some graphic design work... there is something in the OSX settings panel somewhere to change the colour balance to match that of a CRT; don't know if that would help.
[Projoy] That's not my fault. OK, so it is my fault that I insist on using those new-fangled PNGs rather than the old-school GIFs. I think I know of a workaround, but will be fiddly to apply.
[Dunx] I suspect it's because I live in a smaller house than you do :) For the record it's a LinkSys Wireless Ether-G, or similar (the one that's a four-port ethernet hub and a wireless access point). It's in the next room, I would guess about 10m, with a wall and a half in between.