UPDATE June 2015: The links in this post have been broken for some time. That’s not necessarily surprising, as I originally wrote it in early 2011. I’m leaving it up for archival purposes, but don’t bother clicking the links.
Although the College Board’s Questions of the Day do remain archived on the CB site, it’s not so easy to browse them from there. Conveniently, last year someone created a searchable archive that links directly to the College Board’s own archives. It looks like it was more of a one-time project than something that’s indefatigably maintained, but if you’re looking for some more questions written by the actual test-makers during the lead-up to test day, this is a great place to spend some time.
I find the “advanced” search to be the most useful. From there you can, for example, view all Math questions that have been answered correctly by less than 50% of respondents. That’s pretty good, quick access to some decently hard questions. Here’s a particularly brutal one that I give to my students sometimes when they get too cocky.
Anyway, here’s the link. Go nuts!