Came in, saw an overview of some of their software. Lead into a room where they asked what my preference was C or Java. Handed me ~4/5 pages of horrible Java code on triangle objects. It had methods that generated a triangle from given points, computed area, perimeter, etc. Give a few minutes to look over it and talk them through the code and whats wrong with it, how I could improve it.
Lead to another room, given a white board and asked a few algorithm questions. How to sort 2 unsorted lists into one list. Asked to make it more efficient. Asked how to find a given word in a document of strings. Asked to make my method more efficient. Break, lunch with some awkward, bright young employees.
Back to the lab, another room. Asked for an algorithm to find minimum number in a tree. Then Max. Asked if given a continuous stream of numbers, how I would keep track of the minimum at all times.
Each of the 3 rooms had 2 people there scrutinizing you.
I wasn't on my game, one of my first interviews and I did not brush up on anything. Come prepared, rereview over your algorithms. It won't be hard if you practice a decent amount. Talk aloud when you do the problems to let the interviewers follow your logic.