Does anyone have some Ideas on how to rig up a portable power supply for multiple VCRs and Dvd recorders.?

First off, you can buy a battery backup supply (for a computer) and use power strips to power them.... Otherwise lookup how much voltage is requires (after the power is changed from 120 volts, it should be "output voltage", and rig up lith-ion batteries of that voltage.

First, it all depends on how many devices you plan on running and how close they are going to be to each other. I'm going to assume, they are all going to be in a central location to keep it simple. The one thing you are going to need is a gas powered generator that has enough power output to power all your devices and then some just incase you want to add some at a later point. I'm only saying that because the generators aren't cheap, so it would be a shame to get one that does not give you room to grow if you have to buy one. However, you might be able to rent one. Anyway, you can usually use power strips to multiply the number of outlets on the generator, but you should try to keep the load balanced between the outlets. In other words, you don't want to use just one outlet and put everything on it. A better plan would be to split the load between the outlets.