Fedora 17 KDE on my work PC, use KRDC to access a variety of Windows servers via RDP, also have a Win7 test instance running on it via KVM. At home there is a Fedora17 laptop and a PC on the TV running Centos6.
Work is a windows shop, I have a linux desktop (debian) there but it spends most of its time running Win7 in KVM. I'm using SPICE which lets me do dualhead ... and it's pretty good when I VPN in too. Our monitoring and NoSQL stuff runs on linux but the rest is solid Windows.
At home my wife's laptop runs Vista (that's what it came with). My desktop PC and netbook both run debian. Desktop PC does double-duty as HTPC, with a dedicated login that goes straight to XBMC.
Smartphones and tablet (nexus 7) are all android. My NAS/Router is a GuruPlug with dual gigE and ESATA (and a SATA port expander), running debian again. There may be a theme developing here. I also have a VPS or three. You'll never guess what they're running...
I use Ubuntu 10.04 at work. Trying to avoid upgrading because everything "just works". (And, of course, it took some tweaking etc to get there!)
Ubuntu 12.04 at home. Unity is "OK" but would like to try something else (GNOME3) to compare when I have some time.
We use CentOS for servers. Stability and long-term support matters. It's hard to imagine from the outset, but its funny how many machines are still running strong on the same codebase after X number of years. Don't want to break them :)
OS X on laptop. Prefer it over Linux as a desktop, but minor compatibility issues and the fact I can't [legally] run it on Dell boxes means its a no-go at work.