It really depends on the price range you are looking at. I have a cheap Canon 3200F which scans reasonably well and I paid less than $100 for it. It works great with OS X 10.4.1 and Panther as well. In addition to scanning prints it also has an attachment that allows you to scan slides (though the quality is far from amazing). If you just want something cheap that you are going to use once in a while and don't require a scanner capable of capturing a wide array of tones then I would definitely check it out.
Rich