I turn 50 years old in 6 months and have spent the past 35 years sitting on 5 gallon buckets, wooden crates, coolers, cardboard, concrete, blankets, and an occasional rim/tire. I have had it and want a seat to work on my cars.
Please suggest a decent seat that is:
1. Not $175.00
2. Good for a 250# guy
(My trouble lights all suck and I need a new one of those too)

I use one from Harbor Freight...
I actually use an old wheelchair. much more comfy, rolls easily over all the junk on the floor, and I am learning to do wheelies
How about this: http://www.mechanicstoolswarehouse.com/Hydraulic-Tractor-Seat-Creeper-P44549.aspx ?
I bought one on impulse at Lowe's years ago and would never be without one. Lowe's doesn't carry it anymore, but I'm sure it's a generic Chinese thing. Buy the one with the cheapest freight/best color.
Seats that roll. Whee!
What you want is a secondhand skateboard. Cheap, light, conforms to surfaces.
I got one of these on sale for less than $20. Best $20 I've ever spent:

Canadian Tire Pneumatic Roller Seat
I turned 50 three weeks ago, and I don't use a seat, bucket, or even a tire. Toughen up 
I might have to check that Canadian tire stool out. Never seen it before.
fasted58 wrote:
I been using these
those leave waffle like marks on your butt
mad_machine wrote:
fasted58 wrote:
I been using these
those leave waffle like marks on your butt
only if yur stoopid n don't put cardboard or a cooshun on top of it 
mad_machine wrote:
those leave waffle like marks on your butt
That's why you need to stand up for about 15 minutes before your show starts, so you don't distract the audience.
I use one from Harbor Frieght very much like the one you pictured it has held up for four years of professional use thus far and not let me down.
I have a round one like others have pictured, with pneumatic height adjustment. It was about $25 at Sears, during one of their tool sales.
I rarely use it, for whatever reason. Either I forget, or I need to get into position to apply leverage and the stool is the wrong height.
I also have a mechanic's creeper that I've never warmed up to.
50 is in my rear-view mirror as well, and fading fast.
I use a plastic rolling garden stool from Lowes. Cost me $10 on sale and it has big wheels for dealing with the little chunks that always seem to be on the floor. Super-stable.
I've got a Craftsman one that's pretty comfortable and rolls easily.
i also used a wheelchair for a while, but my current garage is so small i don't have room for rolling around. 
I'm glad this thread isn't about other types of "stool."