For nursing school, I used the Scrubzone Energize shoes. They were cheap (under $25), skid resistant (that was a HUGE plus in the shower room at clinicals) and water proof. They're comfy and easy to clean. They are made similar to crocs, but with no holes. Pair them with some moisture wicking sox and my feet felt great! I saw the same shoes in Scrubs & Beyond, but they were a little cheaper online. Several of my classmates had the same shoes.
Now that I'm working, I just bought my first pair of Dansko's & they are wonderful! ($71)