Another option, if you don't like ccsensors would be to use one of those power detection cables that emits redstone if EU is flowing. If you can build a fairly lossless system and know how much eu/t you are pumping through the line you should be able to count the ticks the redstone is turned on for with a computer and using simple multiplication figure out what amount of EU has passed through the line. Not sure how accurate it would be since I haven't tested it, but might be worth investigating.
Can somebody please provide a programme doing so? I'm not too good with computercraft.