I bought a few of these when the nexus 5 came out and they work perfectly for the 6 too.
http://www.amazon.com/gp/product/B00A3NCC5K
non-retarded link
I already have several Qi Chargers I used with my Nexus 5. I have 5 of these spread around my work/house/car.
I bought both the Ringke Fusion and the Spigen Ultra Hybrid. Once I get them and the phone, i'll be doing a comparison video.
I also bought a Black Titanium Dbrand skin. I bought a 32GB Cloud White today, so with that skin I'll essentially have a black phone.
I have a Nokia DT-900 that seems to work OK. It's a little slow, but doesn't really matter for my usage. These were on sale for like $10 at AT&T a year or two ago. I'm also not using a case with my Nexus 6.