I always have a few packs of US-05 on hand and I've recently started keeping some 1056 in the fridge. I'm doing what was suggested in another thread and make my 1056 starters 500ml larger than what's needed. After pitching the necessary amount of starter, I save the 500ml extra, transfer into a sanitized mason jar of boiled/cooled water. I now will always have fresh 1056 ready to go in the fridge and US-05 as a backup.
I might do the same with a Belgian yeast, but haven't decided which Belgian would be my house yeast (1214, 3522, or 3787).
Other than that, when I brew a particular style that calls for a different yeast, I'll just pick it up at my LHBS.