Aw, come-on! LINX (London InterNet eXchange http://www.linx.org) has been
mentioned several time on this list. And Bill Manning has also several
times mentioned http://www.isi.edu/div7/ra/NAPs/ which lists exchange
points for both London and Paris and several orther European cities
(though not Prague).
There are a couple of exchanges in Japan and the Phillipines people are
working on an exchange but have some political stuff to work through. I
suggest you give the above URL at ISI a thorough study. There is a BIG
world out there beyond the borders of the USA.
Consider this a plea for more/updated information on peering points around
the globe. If there are plans for or existence proof of an exchange in
Prauge, I'd like to know.