a few little maps
The Base (from here) A little Doom techbase with some tricky fighting - you need to know where to go to get weapons before you're overwhelmed. Quite top-heavy in that respect. Non-linear layout, uses height variation. Not bad.
A Monster Too Many Small brick/slime slaughter map probably inspired by Plutonia 32. It's far too hard for me but I'll bet someone will make a maxdemo of it one day. Could do with a bit more lighting variation.
SPACESHIP 1024 1024x1024 map ostensibly set on a spaceship; that means silver textures and a lot of windows showing a starry sky texture. Looks good, but the gameplay is a bit unbalanced. You have to kill a small horde of chaingunners and other zombies with a shotgun, and you don't get access to the plasma gun and megasphere until the entire level has been cleared.
Revisiting Phobos Doom episode 1 style map. Mostly faithful to E1 design, apart from using a lot of monster teleporters, and going outside not being optional. Quite easy. You can get trapped behind the blue door at the top of the map, as it is single use but surrounded by repeatable closing triggers. Also the chainsaw is rather useless as you only get it at the end. Summary: decent E1 map, play it if you like that style (I do)
The Killhouse Small cramped dark map from 2001. In spite of that, it's pretty good - although often made up of 64-wide corridors, it's not too cramped, and the light is dingy, rather than absent. Well-interconnected and uses height variation to great effect. Non-linear with plenty to shoot. I remember playing this and it being way too hard, but this is apparently a rerelease with better monster balance. Recommended.