shift register

whats the most bits a serial shift register has?

i want as many steps i can get, say 10,000 or 10^6 , any ideas?

what about a ram stick, its just a bunch of flip flops, maybe i could hook up the out of one and in to the next?

If you need a lot of bits, then RAM memory controlled by a microprocessor would probably be the best way to go, in which case the register length is limited only by the amount of RAM.

How fast does the shift register need to operate?

not fast in computer terms, i was thinking about using ram, since its just a stack of flip flops, i could rout pin 1out to pin2in but i got a feeling ram is more encoded that that, i don't know how to use micro-controllers, i am thinking usb is better/easier way to go?