I've got a full how-to and FREE PLANS at
http://www.iliketomakestuff.com/two-person-picnic-table/
The whole thing was built for under $60 and could be done with only a circular saw and a drill, in an afternoon.
(optionally, a router and sander can smooth out corners)
Estimated Cost
$60
Estimated Time Investment
Afternoon Project (3-6 Hours)
Recommended Skill Level
Beginner