If you would like to have great, clean sounding audio in your meetings, podcasts, or videos. Purchase the microphone and audio interface that I recommend and use below.
Microphone
I use the Audio-Technica AT875R shotgun microphone.
I place it 3-5 inches from my mouth using a boom arm attached to my desk. Since I type on that desk, I use a shock mount.
Since this is a shotgun mic, it works great from a distance. I can position the mic about 6-8 inches from my mouth to get it out of a video head shot which I use for meetings (I have enough room for a lower third with this shot; about a 35mm focal length). But, for best sound, place it only a fist-full away.
Audio Interface
Since most microphones in this category do not have USB, you will need an interface to connect it to your computer.
I recommend the Behringer UMC204HD audio interface. I have the 404HD which has four inputs instead of two. I have yet to use more than two inputs though.
Many podcasters like the Focusrite Scarlett interfaces but these cannot be muted by apps like Shush (see below) and therefore I cannot recommend them.
Boom Arm
The microphone I recommend doesn't come with a stand. In my setup, I have a Rode PSA1 Boom arm. It's fine but if it ever breaks I'll probably purchase a Blue Compass purely for asthetics. Neewer makes a cheap boom arm but I haven't tried it.
Shock Mount
Since I'm typing/bumping the desk I sit at, I got a shock mount which works great with my microphone.
XLR Cable
None of the aforementioned products come with an XLR cable. If you're using a boom arm you will probably need 6-15ft of XLR cable. I went with a 10ft cable from Planet Waves. I had a little cable to spare.
Shush - Digital Cough Drop
When you're in a meeting or apart of a live event, you'll eventually need to cough or sneeze or the dog starts barking or something else will happen, and you will want to mute your microphone quickly. For this case, I highly recommend the $5 app Shush from Mizage.
In Push-to-Silence mode, I have a single hot key that I can hold to mute myself. Great for using as a digital cough drop. Double-press my hot key and it switches modes. Now, in Push-to-Talk mode, I can hold my hot key to talk to my guests (great when I'm in a large group and I don't need to talk a lot). Double-press it again and I'm back to Push-to-Silence mode.
I do recommend turning off the sounds Shush makes which means you have to rely on the status bar icon to know if you're muted.
Monitoring Headphones
You'll want some closed backed headphones if you are going to be recording audio for others to listen to. You'll want closed backed headphones so that audio doesn't leak into your microphone. I've heard good things about the Sony MDR7506. I personally use the Shure SE215 as they are in-ear monitors which aren't so obnoxious on camera.
Too expensive for you?
Another option to all of the above is a USB microphone and some wired earbuds. The Audio-Technica ATR2100x-USB is a hand-held mic that comes with a stand. It has a standard headphone jack for audio monitoring and will work as an audio output so you can hear yourself and your computer's audio in your headphones. It also has an XLR port so if you wanted to slowly upgraded into a boom arm, usb interface, and so on, you could do so without having to buy a new microphone. I haven't used it personally.
(This could be a good mobile solution as well.)
Find yourself saying "I have too much money" or "I want more options"?
Check out Marco Arment's Podcasting Microphones Mega-Review. He uses a $250 microphone with a $880 USB Interface and $1300 headphones with a $850 headphone amp.
While he does have pricey tastes, don't let that steer you away from his mega-review. He reviews almost two dozens mics, ranging from $10-900, with multiple sound recordings from each. If you want to research this rather than take my opinion, look no further. And if you do, check out Podcastage's YouTube Channel.