Lounges and showers for Business passengers:

-ZRH - Swiss Arrivals Lounge
-GVA - outside the lounges on the mezzanine, all airport-run but lounges can get you access - NOTE: they are all inside security (the main checkpoint) but before Passport control and frisking for US flights
-IAD - LH Business Lounge - the downstairs one, yes, in Terminal B no C & D that United use, but the peoplemover or train will get you between them