Any good headphones with a mono switch on them?

I am deaf in one ear. I typically use 2.1 sound, but there are times (e.g. when wife is asleep or watching TV) when I use a mono headset. This is one of those cheap call-center style ones with the mic attached to it. I want better sound when I can't use the speakers, and don't want to lose a channel. Yes, I could mod a headphone cable to join the channels, but I want something nice enough with a warrantee I'd not care to void.
Any product suggestions on what I could use? I'd like something "native" if possible, so I don't need to carry a string of adapters around. Thanks.