My MacBook (now running mountain lion) has been performing very sluggishly for the past few months. It could take up to 3 minutes to start up where before it took 20 seconds and applications could take up to 15 'bounces' in the dock and then a further 10 seconds of the mac loading beachball before appearing on the screen. Its a 2.7mhz 2011 MacBook pro with 8gb of RAM and I have only used 130gb of a total of 500gb available. I have cleared the caches, stopped all login items. reset the pram, deleted all unnecessary languages, cleared any corrupted fonts and used 'clean my mac', yet still the system runs sluggishly. I have noticed this sluggishness since upgrading to Lion from OS X Snow Leopard, which was very fast. I hoped that Mountain Lion may bring back the speed but it but it hasnt. Has anybody got any ideas on how to resolve this issue? Am I missing something really obvious? Thank you in advance.