If you have recently purchased Shimano hydraulic brakes note some new models use a different hose connector than the old ones.
This is the old one:
http://www.chainreactioncycles.com/Mode ... delID=1801
This is the new one:
http://www.chainreactioncycles.com/Mode ... elID=69605
The new one is for the BH90 brake hose has a larger internal diameter, resulting in about 40% greater cross-sectional area. Obviously this can flow a lot more fluid. When I purchased my new XT brakes the new connectors weren't listed on CRC or Merlin's websites and I fitted the old ones by mistake. I had to order my connectors from Rose Bikes in Germany http://www.rosebikes.co.uk/
as few places had them in stock and they were expensive if they were in stock. Rose Bikes sent them via 24 hour delivery and chucked in some free goodies too!
"Sometimes glass glitters more than diamonds because it has more to prove" Terry Pratchett