One of the biggest challenges I have owning a number of devices is that I have a hard time keeping up with which games I own on which platforms. This is especially true with Humble Bundles, non-HB bundle sites, but also PSN and XBLive given there are free games each month that I'll add to my library but won't immediately play.

Is there a single site that I can put in my username across various online stores and it will collate my library into a single list? A bonus feature would be flagging a game I like regardless of platform and it alerts me when it's on sale.

https://www.playfire.com/ tracks your Live, PSN and Steam games.

Stay away from Raptr, they stopped tracking consoles. PC only.

Most of the PC-related services don't have publicly-accessible APIs, making it difficult to pull lists of games in.

isthereanydeal.com can track PC game sakes in multiple sites on multiple distribution channels, so that's a start.

Playfire looks like a good start. Cheers guys.