I installed Steam especially for SRTT, then - if memory serves - purchased Sega Megadrive Collection and Fallout New Vegas GOTY (I still have to most of DLCs!).
Interestingly, back then I wasn't very fond of a fact that I had to install third-party DRM/game managing app just to play something. It didn't take too long for Steam features (Store, community options, sale deals, Steam Cloud) to win me over though.