and of course, there is always the Fung Wah bus - $15 one way, about 4 hours from Chinatown to Chinatown, with a pit stop at Mcdonalds.

http://www.fungwahbus.com I can attest that they move right along as the bus has passed me on both I-90 and I-84. Timewise, may be similar with security and gettting to airport/downtown, but less comfortable, no doubt.