Agreed with OP on HoloPoint and other apps (e.g. AudioShield is another favorite of mine) being a surprisingly intense workout. I sweat quite a bit with these games after ~15min, and this is definitely a problem. On Vive, the soft padding absorbs the sweat from my forehead as a sponge and becomes quite gross. I've learned to deal with the yucky feeling and can mostly ignore it, but I could see how others wouldn't.