I think I still have like thomas was alone and another game somewhere, too lazy to look for them, I saw someone giving away like 10 copies of thomas was alone the other day so I think I'm just going to wait, lol
Been meaning to do it for ages and I've still got some keys in ModBot I've botched up that I need to sort out. At least I know where they are now so I can foist them on anyone. Really, I mean anyone. Take them, sell them, trade them for whatever, just take them away please!
I'd love it if the Steam client allowed you to mark games as "completed". Or just tag games within your collection, I guess. I'm sure something like that has to come eventually, the tagging in the store is probably a precursor.
For me it's "right click, uninstall". Though I did used to have a "Finished (To Complete)" category but outside of the normal games and favs section I've only got a DRM and GFWL set of categories now so I don't get fucked over on activation limits and can keep track on them. If I want to find a game I use the search bar.