Forgot to mention that the plants are in trays.

How long are you going to be gone for? 1 week? If they're indoors and not under too hot of a light, you could probably get away with flooding the tray well, enough that there's still a little water left over on the bottom for them to soak up for a day or two, and then water as soon as you get back. You don't want to do this too often or you'll rot the roots/encourage damping off, but once shouldn't kill tomatoes.

We will be gone for 7 days. I have to keep them outside on the patio--my wife keeps the house really clean and does not want them indoors. I might buy a kid pool, add about an inch of water and place the trays in it. I've also thought about the wicker method, using old cotton socks and a bucket of water. I have 4 trays of different species of tomatoes (~72 plants). I'd like to keep atleast 75% of them. Any adivice on the wicker material or my pool idea will be very appreciated. No way they'll stay alive without water--we are averaging 90 degree temps over the last 4 days.

Sounds like you need a Good Neighbor to "baby sit" those plants or you just may have to start all over again.