Running does not damage knees, and may actually prevent arthritis.

Here's just a sampling of all of the information about this out there:

http://well.blogs.nytimes.com/2009/08/11/phys-ed-can-running-actually-help-your-knees/
http://www.time.com/time/health/article/0,8599,1948208,00.html
http://www.medicalnewstoday.com/articles/136983.php

Boost has libraries for each of these three: sockets through the ASIO library, IPC through the Interprocess library, and threads through the threads library.

http://www.boost.org

The only thing that Boost is lacking for which you asked is a database library.

I'm a marathoner who spends quite a bit of time playing video games.

Do I get a tax deduction for the hours I spend running?

[Citation Needed]