Yeah, me too. I usually get in one of them places and forget what I came for. I'm like a raccoon with a bag of shiny quarters.
Honestly I don't remember where exactly I found it at the Depot (roof ducts, or dryer ducts, ?), but they had a section that had flexible ducting in several sizes.
Sometimes, if it's a short section of ducting, the emission hose for a TAC (the shiny silver tube from the exhaust manifold to air cleaner) has done the trick on smaller ducts.
