Bits over juice starts to take off in trials, though its future is still uncertain: A Washington state public utility is working with a private Internet provide in an inexpensive 60-day trial to see how well BPL actually works, and whether customers will find it interesting. Nationwide, a few dozen trials have about 2,000 actual customers. The future of the technology depends on the real cost and the real speed when it's deployed in the field. Unlike unloaded copper wire, which has known properties, the numbers of systems and the distances involved in BPL add variables that need performance testing. Broadband has to avoid truck rolls to houses to keep costs affordable.