I winged together a table made from the 12' pallets I've mentioned before (first was kidding stalls from recycled pallets, then shelves out of recycled pallets for starting seeds). I have quite a few pallets left and access to more, I plan on lining most of the walls of our 48' greenhouse with these tables to keep the plants off the floor and provide working surfaces. I think the fact that they have slats will work well for draining away excess water.
As soon as it's all presentable I'll do a full write up on the greenhouse. It's been a long time coming. I mentioned acquiring the parts for the greenhouse in early 2008. The level pad for the greenhouse didn't get created until late 2008. In 2009 I talked a buddy into welding the greenhouse hoops to the posts I had driven. It's now approaching mid 2010 and I might actually call it complete. I guess I just really need to hang the door to call the structure done, but now all the fun of it's operation begins. It just shows that persistence pays off!