I've ordered the Timbuk2 Shift, referenced a couple of posts above. The company convinced me that because of their liberal return policy, that I could try it out and if it didn't work for me, I could return it. So, I'll post a full review.

As mentioned earlier, I was also looking for a simple grocery 'go getter', for errands to the local grocery store when my wife forgot/needed something. Today in Dallas, I came across a Topeak MTX compatible basket, which affixes to any rack or links to a Topeak MTX system compatible rack. I had read that if your seat was low, that this would not be a good option. Because it was on sale, I decided to try it. It fits very well, minimal noise, and easily detachable (with MTX compatible rack). Overall, this is a very nice basket with a cutout for the seat. Here are some pics.