Wireless connection problem. Extremely slow wireless connectivity at home and work. Called apple care, they had me delete files:

/Library/Preferences/SystemConfiguration/preferences.plist,
/Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist,
/Library/Preferences/SystemConfiguration/com.apple.network.identification.plist,
/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist

And restart.

You’ll have to re-add the wireless network settings you once had, but this should fix the problem.