was aimlessly wandering through this and that to come accross guys building thier own turbine engines in their backyard, the cheaper ones are being done for $150 or so. Pretty interesting reading. There's alot more info if you do a search. Nothing built cheaply has any real use other than being "neat"

http://www.junkyardjet.com/primitive.html
http://www.ip.co.za/people/kalle/dtt.htm
http://www.reality.demon.co.uk/jet1.mp3 sound clip
http://www.reality.demon.co.uk/gasturb.htm
http://www.reality.demon.co.uk/jet2.mp3 another sound clip, but better