Estimating quantiles with O(1) space

I really thought I found something rather new as I've been looking for such a topic for some time now. But there is a sub-reddit for that http://www.reddit.com/r/CompressiveSensing/

Oh well, it is still interesting and still useful to me to find this term of Frugal Streaming and Compressive Sensing. I can foresee lots of time wasted on this instead of my real project :-)