Not entirely sure where you mean?

My bad - was more of a is there anywhere and if not can we have one? :)

I assume you mean if a game will work in multiplayer across platforms right?

Like saints row the third is cross platform, but you can't play multiplayer between windows and Linux. Or at least when I try, it tells me I am running an incompatible version (even though steam reports the same version number).

If so that would be a nice addition as I have run across many multiplayer games that only work within the same platform. So windows to windows, or Linux to Linux only. Which is and odd way to do it.

Yeah that's it. Was hoping to play some co-op serious sam 3 but don't wanna have to install winblows again!

One game that i can think of that has not cross platform play is Team17's Worms Reloaded; Much to the dismay to myself, my friends and my younger brother, when we discovered it was so, since we all bought it together to play multiplayer.

We would've chosen to get refunds, had it not been for it taking a while before we actually got time together to try to play it multiplayer. But by then we had all played it singleplayer enough to pass beyond Steam's limit for getting refunds.

And it's quite annoying that instead of Steam listing games with "No Cross-platform play!", one have to actually remember to check for the "Cross-platform" ability

[This is a good starting place.](http://store.steampowered.com/search/?sort_by=Released_DESC&tags=-1&category3=27&os=linux) We really need something like [cooptimus](http://www.co-optimus.com/games.php) to catalog cross-platform games.