Mainly just the Paradox Games titles. They go on sale occasionally, but the sales are usually kinda piddly, and always wind up being games I already own. I'd like to see a developer-wide drop in prices for a few days so I can pick up some of the DLC for Europa Universalis IV that I don't already own.
Wouldn't mind seeing The Witcher 3 drop, as well. It's been long enough, right? Right?