When you leave a Tokyo live house rock show, there's usually a group of people outside waiting to hand you fliers for future rock shows. They are members of bands being advertised, or their friends.
I take all their fliers and study them later. I feel sympathy for these people trying to promote something to strangers.
Tonight, however, leaving the Hartfield show, in addition to the usual fliers I was handed a four-song CD-R containing music by the band G-Ampere. I didn't even realize it was a CD until later -- I thought it was just another flier. They want people to come to their show so much that they are handing out CDs of their music, which seems an expensive way to promote themselves but is very cool from the CD listener's point of view.
I've actually seen G-Ampere before, with Hartfield. They've convinced this music fan to check them out again. (Be sure to check out the band's home page, linked above, by the way. It's pretty wacky.)