I'd love to carpool up with someone from Boulder after 11am on Friday. I have a test in the morning and have to volunteer at 1pm and the stinkin' Y bus (see below) doesn't run during the middle of the day. Please reply or stop and pick up the hitch hiker with the "ROCKYGRASS" sign at the intersection of Broadway and 36!
Here's the RTD deal. It's $12 to take the AB bus ("skyride") from the airport to Boulder (per person). The problem is that the Y (which runs from Boulder to Lyons) only runs a few times a day and never on weekends. It leaves the Boulder station at 6:31 AM, 7:40 A, 4:10P, 5:25P, and 6:33P. It's 4.50 unless you ride it back-to-back with the AB, in which case you'd ask for a transfer while you're paying the $12 AB fare.
To make a long story short, you won't be able to use the bus system to get to Lyons on Thursday night. Other options are to stay in Denver at one of the airport hotels and then catch the bus to Boulder and then Lyons Friday morning or to take the AB to Boulder, stay there, and catch the Y in the morning.
RTD's website is pretty helpful
http://www.rtd-denver.com/ once you know about where and when you want to go.
If you decide to stay in Boulder and wouldn't mind camping on a lawn, I live about 200 ft from a major bust stop, send me an email at colesigmon "at" gmail dot com. (It's really @ and . but you never know about the spammers...)