Interesting little article from azcentral.com about breweriana—basically just an introductory piece. "Breweriana" is simply a more complicated way of saying "beer collectibles."
From the article ("It’s all about the beer"… heh):
There are print ads, ashtrays, bottles, cans, caps, clocks, coasters, posters, tap handles, mirrors, coolers, hats, playing cards, tin signs (the older the more valuable), shirts, bar towels, drinking glasses, openers (either hand-held or the kind that attach to a wall) labels, patches, beer steins.
Do collectors zero in on any specific rare memorabilia?
"It’s the rare and limited kind that we look for," Barnes said. "Pre-Prohibition items that date prior to the 1920s are really valuable."
Collectors travel all over the country looking for things such as old tin beer trays, cans from the United States and cans from foreign countries. They make several trips to swap meets in California to find these items.