alea it has occured to me have have not given the tmer that would lead a good google run on this for you and your readers. Pyrosequencing e.g. is directly familiar to me (yes as awk opines with deliberate degradation, I am an expert on everything
)
but seriously, any person should simply read the current wiki entry, it is positively dazzling
I personally, cannot believe the things that a fool like I (not me specifically) can have done, essentially for free,
http://en.wikipedia.org/wiki/DNA_sequencing