Mostly Maths is a personal blog on programming tools and habits, covering Plan 9, Emacs, Taskwarrior, timeboxing, and blogging.
HN links it for posts like the Plan 9 plumber write-up and a browser demo; commenters give no strong opinion on the blog.
My girlfriend (and myself, but only at home) use a gym ball as chair. Of course I can't recommend it to everyone, and long stretches sitting on it can be really tiresome. I wrote a blog post at my blog, you can check it at http://www.mostlymaths.net/2010/08/gym-ball-as-office-chair-review.html
It has worked wonders for small back pains in the lower parts, and also for some head aches related to spine problems, for me.
Give it a try, a gym ball is inexpensive.
More specifically, Plan 9 devised the plumber framework for copy+paste and similar IPC.
https://en.wikipedia.org/wiki/Plumber_(program)
http://www.mostlymaths.net/2013/04/just-as-mario-using-plan9-plumber.html
I expected the demo would be embedded in the blog post, but it wasn't. Here it is: https://mostlymaths.net/sketches/iris/index.html