I've been looking at a few options but seem to have narrowed it down to the following three:
Restoration Hardware: A classic sheet set. I like that it is simple and understated.
Pottery Barn: A small variation on the Restoration Hardware set. I like the small detail that adds a little twist to the original.
Land's End: These are oxford cloth sheets. Much different than the other two but still simple and clean. I had oxford cloth sheets when I went to college and have been thinking about getting more ever since. They were just great to sleep in.