I have used a snare hit for "4" in my counts for, oh, ever it seems. Nobody ever seems to mind. "1, 2, 3, BAM", song starts.
We came up with this for an album cut once. The drummer screaming count off to the choruses.
if i know a song is in say G i will look at the bassist and say 'ready? you sure? okay ... this song is in the key of E!' and watch him sweat the first bar!
j