I've noticed there's always a lot of interest when the team posts flight sim related content, but not too much intent to try and follow suit and get into it. I think the general idea is that flight sims are comically difficult, and since they require some specific hardware to enjoy there's this nervous consensus that flight sims are for weird people.
It's important to know that flight sims are a broad spectrum of games, and not a single, defined genre. The necessity for specific hardware scales with your expectations as a player, but the baseline of a working flight stick remains key. What you bolt on top of that is entirely up to you; TrackIR is a defining part of the experience, but i've flown with excellent pilots who don't have one, so it is not a requirement.
I just want to write a short rundown of what you'd actually need to get into this, if you were curious.
Flightstick or 360 controller
There's no escaping it... You need one of these things, or you will not be effective, and your enjoyment will suffer as a result. Modern sims typically offer an Xbox360 controller scheme, and I used my 360 controller when learning to fly the Ka-50. Eventually though, the range of motion you get from a thumbstick simply isn't enough. Regardless on your choice of simulator or even your choice of aircraft, there will be a moment where absolutely minute motions on the stick is the difference between a botched landing or a round missing its target. This can sound dull to some, but I practise archery in real life, and a big part of the enjoyment of archery is fine control of your motor skills. Think of it as a subtler approach to something like a fighting game. It's accepted to get a stick for fighting games, because it is acknowledged that the skill is largely motoric. It's the same thing with flight sims; It feels amazing to be able to do super tiny adjustments confidently with no oversteer.
The most common modern stick, I think, is the Saitek X52, which seems readily available. Hopefully others I fly with like or can chime in on this. I picked up the Thrustmaster HOTAS Warthog stick+throttle, but I'm a crazy person, and I've found maybe having a more generic stick helps you get into a bigger variety of sims with less difficulty (the Warthog stick is an A-10 stick replica).
A fairly modern PC
PC flight sims are not necessarily visual tour-de-forces, as Brad described it. The hardware demands come from intense physical calculation on the CPU, depending on the sim, and as such a fast processor is the key. Most modern sims make use of 64bit processors. Having at least 8 gigs of RAM is also highly recommended. Any modern graphics card from the past couple of years will probably do you just fine.
A flight sim
This is where personal preference comes in. Do you want a super technical "study sim" clickfest where simply getting off the ground is a challenge? Do you want an arcadey shootybang with lots of planes to choose from, ala Ace Combat? Do you want a languid joyride without any risk of horrible murder?
An excellent entry point in any case if you are new to flying is Microsoft Flight; It's free to play, teaches decent fundamentals, and gives you a sense of the tempo of the thing. I'm a big fan of the Ace Combat series, and those games have a furious pace that has practically nothing to do with simulation; Jane's Advanced Strike Fighters approaches this accessibility, and is about 20 bucks on Steam now.
If you want to dig in deeper, it becomes a question of time frame. I've never been a fan of WW2 planes, but the IL-2 Sturmovik series is apparently super good and hardcore. I tend to favor study sims focusing on a single plane, so I'll buy sims based on what aircraft they are simulating; Right now I'm neck deep in the DCS series, namely DCS Black Shark (Ka-50 attack helicopter) and and DCS A-10 (the quicklook is probably notorious by this point). On the far end, there's the Falcon 4 BMS modification; Every time I watch youtube videos of organized multiplayer BMS flights I get the feeling that that's just too far even for me.
And that's it!
You need a PC, a controller, and a game. Getting into flight sims does not require you to leap head first down the rabbit hole. There is certainly a rabbit hole nearby, but the choice of jumping into it is entirely yours. You don't need crazy hats, dedicated rooms, or any of that jazz.
But are you a simmer..?
This is the big question though. There's no denying that flight simmers are a special kind of player; We savor mastery above all else. Learning to fly the A-10 made me read 2 books about A-10 operations over Iraq and Kosovo, and the flight manual PDF is always with me on my phone. The pleasure comes from climbing the learning curve, from constant improvement. It's comparable to that of a Starcraft player, or a fighting game player. We all crave improvement and mastery. The biggest difference, I think, is that with a sim the skilful operation (or lack thereof) of the aircraft is the biggest enemy. In multiplayer, which more often than not is cooperative and very friendly, we're all in it together. We ask questions, help one another, laugh at our own mistakes and share videos and screenshots of epic victories or wild fuckups. It's actually the friendliest community of gamers I have ever encountered, I think, because the emphasis is so clearly on cooperation.
It's one of those communities where players who are better than you are HAPPY to help you, because they get to show off their knowledge and skill. If anything has made me jump in, it's been understanding that the water is indeed fine: If you are going to mess with sims, you really need to get online! Join a community like http://flight-sim-fanatics.com, introduce yourself, ask questions. Hell, join the community before you even get a game. Your choice of community will likely inform most of the choices you make beyond that.
So yeah, don't be afraid to join up! It's undoubtedly a big wall to climb, but there are lots of fellow climbers, and the climb itself is a real journey.