You can use two metal joist hangers to convert a couple of sawhorses into a temporary but sturdy work table. Buy the hangers intended for 2x4s, and attach one to the middle of each of your sawhorses along the top brace. Fasten the hardware with screws. Now slip a piece of 2×4 into the hangers to form a cross brace between the “legs” of your table, and rest a suitably sized piece of plywood on top. For a sturdier table, use two sets of joist hangers positioned near the ends of the sawhorse top braces instead of the middle.