obviously something with a very broad customer base like newegg is an optimal target. its easier to get pledges and its useful to more potential bitcoiners.
this is all very us-centered though. i wonder if we can get some good suggestions and possibly pledges for germany. it has a lot of bitcoins, so maybe a not-too-big online hardware store or supermarket might be convinced.

for hardware i would suggest notebooksbillger.de or mindfactory.de, for food and general goods i can only think of lebensmittel.de or gourmondo.de. if i get some good suggestions or pledges i think we can start a thread in the german forum.

i also wonder if there are any good targets, virtual goods stores or online shops that have, for some reason, an appeal to customers worldwide.