I suggest you have someone (not yourself) examine your machines (Apple or PC all the same) "Flash Cache" .... stored as "*.SOL"(star-dot-SOL) files.

ALL flash (macromedia) (youtube etc) has an isideous "ET Phone Home" aspect (ever see "google analytics" flash across your loading tool bar?)

Have your friend do a "Search or Find" beginning at the root of your HD....

Sincerely,
Gargoyle

To paraphrase Ferlingehtti, Hard-drives, are very much like underware .... when you REALLY get into them .....some very shocking things come up.