Tuesday 22 February 2005 10.49am
I'd say 450 pixels. This ensures that the pages don't get stretched for those viewing the site at 800x600 resolution.
(Though I have a 1024x768 screen I have my browser window set to 800 pixels so I can see other windows at the same time)
For anything bigger than 450 pixels across, just provide a link to the image, rather than including the picture itself in your message.
Edited 1 times. Last edit at 22 February 2005 10.50am by James Hatts.