If you are like me and purchased Apple TV 3 when the Dicksmith deal was on and have since only tried to setup only once because it is a good looking paperweight without the jailbreak. Then wait I have some news for you.
There is air parrot which showed some promise but the quality of HD videos was dismal and then of course there is Mountain Lion upgrade but air mirroring is only supported by newer specs of Apple products i.e. June 2011 onwards.
And so I stumbled on this little beauty and what a beauty it is.
This app is only available for Mac (sorry PC), and you can just drag and drop any video and it plays on your Apple TV 3 in glorious 1080P (it brings tears to my eyes). Try the software before you buy and you will know the difference.
This product when initially launched was $7 USD and recently a more mature version (as per the newsletter) was launched with all the bells and whistles (sans subtitle support as they are still working on it) but they also increased the price to $15 USD.
I was upset because I missed it only by days and when I was trying the software but they sent me a newsletter with some great news.
The app is now back to it's original introductory price of $7 USD for the first 100…err.99 customers.
and the good thing is that this is a personal license and you can use on all personal macs you own.
Link for the deal - https://sites.fastspring.com/tupil/instant/beamer?coupon=WAI…
Thanks OP - looks good - my little people are watching something I hadn't gotten around to converting right now.