Two ideas come to mind:

Water Cooler Method:
Use seed trays or any containers to put both your plants and the reservoir in. Poke a hole near the bottom of a bottle (size dependent on how long you're leaving for). The height of the hole will determine the water level in the seed tray. Once the water level reaches the hole in the bottle, water will stop flowing and the water level will be maintained as long as there is water in the reservoir. Same idea as a water cooler.

Wicking Method:
Pot your plants with some cotton string dangling out of the drainage holes. Place the ends of the string in a tray or bucket of water, and water will wick up the string into the pot using capillary action. To keep the string from accidentally pulling out of the pot, I loop it through some non-slip mesh you can get as drawer liners in the kitchen department.

I hope this helps, you can use whatever method would work best for you. Water bottles if your plants might get root rot, cotton string if you don't mind repotting. Or hey, go for both and use a reservoir in a tray that feeds wicks :)

I meant you can use water bottles if your particular plants don't mind having their feet wet (where root rot is NOT a problem)

Ceramic watering cones or capillary mats work pretty well. I'd still have someone check every couple of days to make sure the water lines aren't clogged, the reservoirs aren't empty, etc.

I would suggest just getting a large water reservoir, say 20 gallons, and put in a pump on a timer, and run restricted-flow drip lines to your plants. 15 minutes of slow drip twice a day should set you fine for a week or so.

My husband built an oblong box about 4" deep. long enough and wide enough to fit under 2 double 48" long fluorescent fixtures. Covered bottom and sides of box with pond liner. We cut up plastic garage storage shelves to fit inside pond liner. Each section (3 or 4 sections) needs a little space on side and end. Get Capillary cloth and cut so cloth will hang over into water. Fill container with water, put lights on timer and you should be good for a week or two. Depends on size of plants and water reservoir.

I have used both the wick method and capillary mat technique with good success. The wick method works great for larger individual plants and the capillary mat works really good for cell packs/starter plants.