Perhaps most useful portable lighting kit: two self-contained 400 w/s monolights with built in optical slave; two 6 foot light stands; two white-black umbrellas and all the connecting cables all in a single canvas carrying bag. The whole system weighs less than 18 pounds.
The monolights can be triggered by on-camera flash or by the included camera PC cord. Radio receivers (not included) can be connected via 1/4" cables.