Nuclear Throne is a post-apocalyptic rogue-like with a retro, 8-bit art style and guns, from developer Vlambeer (who we've mentioned a few times before). Really, what more could you want from a game? Well, probably a video of how it plays... which is exactly what you're going to get.
Currently available on Steam via the service's Early Access, you can try Nuclear Throne yourself if you don't mind parting with $US12.99. Otherwise, Eurogamer's Christian Donlan has put together a 12-minute Let's Play, which you can check out above.
Gameplay is top-down and 2D, similar to titles like Crismonland, where one moves with the keyboard while positioning their reticule with the mouse. It looks pretty polished already, though Donlan notes that you can't change the resolution and playing the game involves using half a control pad and a mouse, which doesn't sound like the most comfortable arrangement.
But he seems to get around alright, so it can't be too bad!