I have a long-arm on my wish list, but in the meantime, I quilt everything on regular domestic sewing machines.
My favorites are the 15-91's from the 1940's - more room than any other of my machines. But, the Kenmores from the 1950's and 1970's are really good for FMQ, too. The Lady Kenmore has the smallest area under the arm, but even so, she managed a queen or king sized quilt. :)