Viet was right - it's the ABS self-check routine. Activates at 7mph. Present on all Accords w/ ABS (and probably all Hondas with ABS; Tink's post seems to substantiate that w/ his Ody). System was present at least as far back as the 6th-gen Accord; I had it on my coupe, but never actually heard it until the other day in this car.
Was actually going to post this last night, but the 'Furry Green Monster' ate my post (again)

, and I figured I'd just consider the issue 'resolved'. Then I saw more responses, and figured I'd provide confirmation to the group, rather than see more people guess as to the cause (as if I were a Honda engineer, or something...)
