Here is my set-up for an automatic watering system for my Nepenthes. This system allows me to go on vacation and abandon my plants! The main drawback is the unsightly nature of all the tubes. I elevated the plants just above the water line by using a grid which is sold as a cover for flourescent light fixtures. You can cut these up to size with clippers. There is about four inches of water in the tank.
First get yourself a 55 gallon aquarium (used ones are easy to find on craigslist).
I use two four-foot long T-8 fluorescent fixtures with (4) 32-watt bulbs.
I collect rainwater off my greenhouse roof to fill the reserve water used in the tank. Since your water will be recirculating you want the original water to be as pure as possible.
Purchase one of these digital timers for about $20. You can program them to turn on for as little as a minute, and you can set what days you would like to water.
Purchase a submersible pump for about $20 and plug this into your timer. Make sure the pump is completely covered by water before you turn it on.
I went to a hydroponics store to purchase many of these items. It is really useful to have someone walk you through the process. If you don't have one near you, there are sites like this one that have most of what you see here.
Attach this special white tubing to the pump and seal the other end by folding it and tying it closed with string or a clamp. Use the sharp yellow poker to make a hole in the main water line (white). Insert one small black tube into the big white tube. This white tube is a special material that seals itself around the black tube so it doesn't leak. Run the small black tube to an emitter (the long pointed black plastic thing) and poke one emitter into each plant. Also shown is a scrap piece of grid which I set my plants upon.
Here is a close-up of the individual black tubes that run from the white main-line to each individual plant.
Here is a close-up picture of the emitters.