I thought about extending my electroglo staff, but I didn't think the LED's would be bright enough for a longer staff. However, after reading all the great ideas in this thread, I'm off to the hardware shop.
I think I will try fitting some of those photon micro LED flashlights (like the ones at the HOP shop) to a length of perspex tube or clear plastic tube or whatever.
A bit OT, but the best idea I have seen recently is the glowstaffs that Farrah Siegel used in COL 2. The LED's appear to be located about 6" in from the end of the staff, instead of at the end of the staff. So, you can grip the staffs by the end and spin them like poi, or you can grip in the centre and twirl like a staff. The best of both worlds I reckon 