Cheapest I've paid lately for 40gr Mini-Mag is $5.90/100rds plus shipping... there should be better deals out there, but I just decided to pick up a case in a pinch.

Federal Game-shok 40gr (almost equivalent to Mini-Mag) can be had around $5.58/100rds last I saw.

Someone was saying in another forum there might be CCI 40gr "Tactical" on sale at Cabela's this week or next (brick and mortar only) for $17.99/375rds. Not positive on this one since I don't have a Cabela's locally.