What software do you use to do the resizing, Simon? I use Photoshop Elements 12 (I think but it could be an edition or 2 either way!) and resize to (usually) 900px (pixels) x 600px before a final sharpen (if needed) and saving. It's at the save step that the final file size can be worked on - I Save As a .jpg and in the dialogue window that opens, I tick the Preview box to a) see the final product (I zoom in to 100% to see the image at the final size so I can see at what point oversharpening creeps in and back off a twitch!) and b) see the file size. If it's over 350kB (I think that's the forum limit), I knock the quality back and see if that's far enough without impacting on image quality. If I can't get the file size down far enough, I simply don't bother any more - I dislike sharing shots for small screen view enough as it is (far preferring A4 or larger prints as a viewing option.)