Oh yeah, I've built a few...the best I liked was I have this space between two doors in my home leading to the basement that's big enough for a 1x12", that works pretty well. I just put an old mattress and the 12" cab there and it worked OK.
But, ultimately, it really is best when you also have a mic farther away, never did get the sound I wanted that way, in a closet.
Dee
"When life's a biatch, be a horny dog"
Amps: Marshall JVM 410H w/ Plexi Cap mod, Choke Mod & Negative Feedback Removal mod, 4x12", Behringer GMX110, Amplitube 3/StealthPedal
Half a dozen custom built/bastardized guitars all with EMG's, mostly 85's, Ibanez Artwood acoustic & Yamaha SGR bass, Epiphone Prophecy SG, Vox Wah, Pitchblack tuner plus assorted pedals, rack gear etc. for home studio use.