My recommandations, in knowledge of Philipp's situation :
  * I came across a box of Token Ring and Arcnet stuff.
Mostly NICs. 
Scrap
  * IBM PC AT and around 
Original IBM AT ->
Sell, others scrap.
  * Sun Ultra 1 (or 5?) pizza boxes 
scrap
  * 5.25" and 8" disk floppy drives and HDDs
Good MFM drives & 8 " floppies are getting somewhat thin on the ground,
5": scrap
  * Philips P4500 computer (or 5400?) 
Will sell on
Ebay for a token amount.
 Is there any interest in that kind of stuff? Might that be of
 sufficient quality (quantity isn't the problem) for a dedicated flea
 market event? 
In short : good, decent size MFM drives might be worth your time, the
rest rather not.
             Jos