Great community site for the free MTGO format Heirloom. Run by great community activists that give away money twice a week at free events and maintain the format for no compensation of their own.
Pretty good for an internet forum that lets you talk about anything at all. Well organized, moderators are fair and you really are free to have any opinion you want so long as you aren't just attacking someone like a 7th grader.
The card search engine is usually not working and full of bugs. The program itself is full of bugs and difficult to use. If you have a lot of time to invest it can be worth it I imagine but I didn't like it at all.
The moderators on the forums are basically self righteous fascists but that's not that uncommon so I'll only ding them a little for that even if it's a huge annoyance to me. It's slightly more annoying with them in particular since they like to act as though they are the ministers of what is acceptable on the very edge of political and social discourse. Otherwise it's a great comedy site. Maybe the best.
Great article site about MTGO, the online magic the gathering game. Anyone can become an article writer there and get modest compensation for it. You have to be able to create a worthwhile article of course but they do half the work for you by giving you access to their top notch article creator software. A great community resource.
Best site for magic videos and articles there is. Contributors are the top MTG players playing the game today. No annoying subscription fees or irritating mechanisms to force you to look at their products constantly. All good, no bad. (Get adblock on your browser autoblock ads on their videos)
Site has more interesting unique user made games, music and movies than you could ever absorb. Lots of great quality stuff, makes the stuff people try to charge you for look like complete garbage.