I have my clsuter at IP Exchange (http://www.ip-exchange.de/) in germany. Puts most "professional" US data centers at a shame.... 16,8gbit external bandwitdh on about a dozen links. Sadly, they only rent out rack SPACE (plus possibly hardware through a deal with Dell). Nothing for smaller setups. They have good speed to german stock exchange, though - less than 10ms 
I am more than happy with them. I pay around 600 USD for half a rack including 1000gb traffic and electricity NEVER had an issue at all. They are one of the few actual centers that does support high density systems if asked for - i.e. they can handle racks full of blades, where most centers go nuts on the cooling needs per rack
They have a branch catering the end user (only in german, though) at http://www.ipx.de/ - but it is not necessarily high quality (though the servers are decently priceed for what one gets).
I am more than happy with them. I pay around 600 USD for half a rack including 1000gb traffic and electricity NEVER had an issue at all. They are one of the few actual centers that does support high density systems if asked for - i.e. they can handle racks full of blades, where most centers go nuts on the cooling needs per rack They have a branch catering the end user (only in german, though) at http://www.ipx.de/ - but it is not necessarily high quality (though the servers are decently priceed for what one gets).
