John Romero, recently made a new DOOM map in 21 years. Pretty cool stuff.
You can download it here:
http://www.doomworld.com/e1m8b/e1m8b.zip
And to those who aren't familiar with playing custom DOOM maps...
1. Make sure you have the DOOM.wad file and any DOOM source port (I recommend zDoom: http://zdoom.org/Download )
2. Download the map
3. Once you download it, double click it and open it using zDoom.
4. Open up the command line and type in: MAP E1M8 - PHOBOS ANOMALY