Heck, most of 'em are a buck apiece   I agree, great source for cheap plaques, I do the same thing, buy a stock of them to have on hand.

I like Michael's 40% sales, too.  You don't necessarily need the flyer or a coupon, usually things are marked down.

I like to get the smaller display cases from sales at Michael's, too.  The football (American football, for our Commonwealth cousins) case is a good size to display 54mm figures, or other models.  I stocked up on those, and the baseball bat display boxes.

Michael's, AC Moore and HobbyLobby are all good places to find modeling supplies, and odds and ends that can be used for modeling (need Greek columns, for example?  Michael's carries Wilton cake accessories, including columns in three sizes for wedding cakes).