Hello all. I've been quite delayed in doing this as I started off in the Mach5 section. I originally came here to look into using an 18" car sub as a home theater sub and ended up with good results. I was given a link to http://www.hometheatershack.com/forums/diy-subwoofers
with info about previous Mach5 sub builds and found a lot of good reviews on the build. I'm now finalizing my payment with them and hope to have a sub by end of next week. I'm under the same name over there (I think), and I will certainly post build pics for all to see (thinking sonotube build). I have all sorts of crazy ideas like taking leads from rumble controllers to a sub with an audio processor inbetween to generate the appropriate rumble.
Other interests include Architectual engineering, building computers, cycling, musical instruments (any), recording engineering and random stuff that gets my fancy (usually involving bastardization of existing technology). One thing I'm doing with this sub is generating an 18hz sine wave as that is the resonance of the human eye and makes you see funky things.