It rather depends on all the information you know about before the interview(what do they use, what kind of questions did they ask in the phone screen, what do

It rather depends on all the information you know about before the interview(what do they use, what kind of questions did they ask in the phone screen, what do you know about the company). If it is for a specific language position I typically read the books I have for the lang. Practice problem solving techniques (something along the lines of prag. prog.'s code katas.)