I could watch two hours of Roberto Benigni's character in Down By Law (1986) talking to just about anyone and love it. Though director Jim Jarmusch, in his wisdom, provides John Lurie and Tom Waits as the straightmen for Benigni's confused foreigner, first in prison, and then on the run. Waits and Laurie also provide the soundtrack, and it may go without saying that it's really quite good. The whole things good. Watch it.
Then listen to Lost in Criterion discuss it.