I was just made aware that there is a new LED/LED strip that should be very helpful for people that want to make POV installations.
Here is a nice article describing it on Tim's Blog
I have bought them on fleabay in 100's quantities for my clock project (cue collective groan) They seem to be pretty straightforward re: usage. The only downside is that for reliable operation you really need two external transistors to address them (one for the clock, the other for the data signal). IIRC, Paul is going to address that issue in a coming 'peripheral' board for the Teensy 3 series by adding two 5V buffer chips to it. The benefit is much faster / robust response than the 1-wire approaches used thus far.