anything that keeps your mind active.
Physio graph charts (the good old up/down arrow charts for all dx's)
Pharm Cards (BRS and Kaplan or what ever type you like)
Micro Cards
Most important of all... Questions, Questions, Questions, Questions
Do questions in this order... USMLE world, Kaplan, Usmle Rx
And do NBME's/USMLE world Assessement exams sequentially early.. i should of dont my nbme earlier but i did mine a month before exam, which gave me time to repair behavioral before my exam.. i did my Kaplan simulated exam 5 weeks before the exam and only got 63 percent on it.... The new simulated exam is harder from there old one i think since it now has 46 questions and now video and sound q's on it.. but I ended off with a 223 (520) on usmle world assessement 4 days before my usmle.... so im hoping i passed and did well... my exam had some evil 2 hard questions on it.. but alot of questions, specially micro seemed really easy...
But some of the questions i did would of been evil if i had not done more than 1 qbank.... Uworld is excellent for the harder q's on the exam.. but the majority of the questions on step 1 were more like kaplan/usmle rx.. @ least thats how i felt.