yeah it is... would work better with oil or hash tho.... i don't see the point in it tho.. but you asked if it's possible and yes it is...

all freebasing is, is take a spoon, or some foil, or a lightbul as mentioned above, and putting a flame under it til it produces smoke... again, id on't see the point... the reason for freebasing is for drugs that can't be smoked in a conventional pipe, or atleast not without wasting alot of it... etc etc...