Apart from the usual websites that I can always be found lurking around on, such as Livejournal, AO3, Fanfiction.net, Facebook etc. There is another website/app that I'm spending a fair bit of time on at the moment, and - shock horror - it's nothing to do with fandom!
After my charity events last year, I thought about how I could still have the motivation to keep active, without needing to train for a 'run' which I loathe with a fiery burning passion!
And I found:
They have a series of distance-based virtual challenges which you can sign up to do. You can link your Fitbit or whatever fitness tracker you use into it so all your steps count as well as any gym or other workouts.
So far I have completed Hadrians Wall (81 miles) in three weeks and English Channel (21 miles) in six days and the best part is you get these absolutely gorgeous (and very heavy) medals when you complete your challenges.
I'm currently on Lands End to John O'Groats (1,083 miles - the scenic route), and I just got an alert yesterday morning to tell me I'm 20% along. I've set myself a target of 30 weeks in which to do it, and that works out at just over 5 miles a day - in whatever form those miles take.
There are lots of other challenges, not just British based ones, such as Great Ocean Road, Inca Trail and Route 66, and I hope to do all of them eventually!
You can also track your progress on google maps through the website and see your position on streetview, and every now and again, when you pass a point of interest, your get virtual postcards. And there's a great Facebook group that's very friendly and motivational!
So yes, that's a website that I've been spending a lot of time on recently, and hope to do so for the foreseeable future!