Oh, have you tried other channels? In my neighborhood, because of the density of wireless 'things', I'm on channel 9 which seems to be clear of interference.
As for placements, I moved mine to the attic after getting frustrated in trying to get a signal around a chimney.
Yup, tried 'em all. 2 neighbors are broadcasting on #6, so I tried everything else. No luck.
After talking to Belkin tech support today (hint: If they list their tech support's number prominently on the front of the product box it means either 1) that you'll never get through to them; or 2) that their tech support sucks. My experience was the latter) and getting nowhere, I'm going back to the Linksys router and possibly a different PCMCIA 802.11g card.