Sure enough, I did.
Two things in this shot of Matthew Broderick's boss. First is the baseball he's holding -- a reference to the ball Ferris caught at Wrigley Field and later used to turn off his stereo. Also, just over the Mr. Linder's left shoulder is one of those static/lightning globes (I forget their proper name) much like the one found in Cameron's bedroom.
Still in Mr. Linder's office, there's a lamp shade featuring what appears to be some sort of rough sketch on it.