Randy and Evi Quaid -- Let's Bail!

TMZ has learned Randy and Evi Quaid posted bail moments ago -- and the Presidio County Sheriff was kind enough to drive them to an ATM to speed up the process.

Law enforcement sources tell us the Quaids each posted their $20,000 bail -- they were arrested earlier this afternoon in Marfa, Texas after arrest warrants were issued for them out of Santa Barbara County, CA.

And get this: We're told they hammed it up for their mug shots, smiling and laughing as they took multiple pictures.