I'm a variety vaper. Most days, I'll touch at least 7 ecigs and many at different voltages with different attys, cartos, or tanks installed.. By the end of any given day, I will have used at least half a dozen different juices. That said:
Everything I bought this last year is a favorite to me in some way. I bought some really great kit during 2011
Chronologically:
1) 510 starter kit with PCC - I used it almost excusively for a couple of months while the ego-t was coming to market. PCC cases are handy if you want to keep the same old feeling of having to carry a pack of smokes, Some people do need to have a cigarette pack with them as part of their addiction. Not smoking, but knowing you have your pack nearby is far less stressful than just not having a pack nearby. A pair of 510 batts and a PCC Case that holds a couple of extra attys and cartridges = a nice portable product that still has the feel of carrying around the familiar pack of smokes is a pretty good kit for a lot of people.
2) Ego-T I'm not sure how many times I've typed this on ecf: Mine were trouble free. My one and only minor complaint is that it muted flavors. I remedied that by using stronger flavors and my t's did fine with stronger flavor juices. For me, the ego-t remarkably consistent and reliable PV.
3) Rough Stack V2s (I have 3 of them - two maxis and a regular). Great product that can stand up to some serious abuse and that has good battery compatibility to give the user lots of voltage choice. No significant difficulties to report after having one of those with me or near me at pretty much all times of every single day for the last 6 months. They've taken insane abuse from my work and pay - most of what i do is physical... Money Well Spent.
4) Old Goat bottom feeder. It didn't have a long life, but it introduced me to bottom feeders. It was a great little mod and I'm going to buy another to replace it even though I have more durable feeders now.
5) MAP Tanks rate on my list of best gear I got in 2011 - CE2s are one of those thing that just doesn't fit in a box anyone can call "all good" or "all bad". When you get them to work, not much compares to them in vapor production... But most people don't want to have to tinker with them to get them producing properly. The MAP tanks take all of the wicking problems out of the equation because you can actually see if your wicks are wet or not. The vapor they produce isn't for everyone - I don't know how to say this, so I'll risk sounding stupid: The vapor feels fluffier, cooler, and smoother than vapor from an atty or a filler carto. Vapor from other devices feels warmer and denser... So, the vapor from a CE2 isn't for everyone, but I like it quite a bit sometimes.==== The other reason I say MAP tanks is that I don't think it's likely that dual coil tanks and now single coil tanks probably wouldn't exist if someone wasn't looking at their MAP and wondering if they could get a dual coil smoke tech standard xl sized to work in it...
6) Kalamazoo Triple-V. It's bigger than the silver bullet. It has the same switch as the BB (arguably the best horn switch possible). It has a nice deep juice well. It is highly reliable and probably indestructible. In my opinion, I think it is the nicest 5.0v tube mod out there. I got a nice deal in the classifieds on that one. It's not only a keeper but also a device I use very, very often at my desk at home. --> This one rates as what I consider to be my best buy of 2011 for a couple of reasons. First, I think kalamazoo could sell them for a hundred bucks and people would pay it. They go for 75 - I got mine for 60 shipped. It's a really nice mod.
7) REO Mini. I've only had my REO a short while, but I've been taking advantage of its features pretty much every day. The joy for me in the REO is that it is the single best hassle reducer I've owned for vaping. I can fill and put on a 2.0 ohm boge and fill the 3ml bottle for a total of a little over 4 ml of juice in one device. I carry one spare battery (and not some huge batt either - just a 14500) when i leave the house and some days I bring a spare atty in case I want to use a 306 for a while instead of my cartomizer. An atty and a battery both fit in a 2xAA storage box, so I don't have to carry much kit to know I'll get through the day.
I have various other items purchased or traded for over this last year that might deserve some honorable mention, but they just don't make the cut as "Best Gear"