Use It lists the top 10 web design mistakes for 2006 with a lot of good ones to boot! Notable pet peeves include poor search on sites (I’m guilty when I don’t use Google on a site), PDF files (ditch ’em everyone!), poor usability by not changing the color of visited links (guilty here), and force opening new browser windows (annoying).
If I can change, and you can change, we can all change… Hit the source link for the goods.
UPDATE: Added forgotten link. Whoops!