Right now copious amounts of Doom, namely Project Brutality. Been enjoying it on a number of mappsets. I'd say Guncaster is still probably my favourite gameplay mod, but PB is solid. Basically a vastly superior version of Brutal Doom, complete with weapons upgrades and more powerful enemies as the maps go on. First time I've seen a mod do that, adds a real sense of progression, alongside being fun to play. Can't wait for the Starter Pack to be released so I can play PB with it, I think that will surpass many modern shooters in bombasticness. Although I already have over 300 megawads in my Doom folder...
Alongside that, I finally got Neverwinter Nights 2 to work (I literally just had to copy a DX DLL file into it's main folder and it booted up. Horay!). Instead of playing the OG campaign I went straight into the Baldurs Gate Reloaded. Very solid adaptation. No idea why NWN2 gets all the hate either. The camera is perhaps slightly clunky but otherwise its very solid and everything is very customisable. I also got a bunch of other campaigns, including an Icewind Dale remake, so my RPG itch is going to be scratched for a very long time.