Setting environment variables in Mac OS X

Once you have experience (or not) with some uX system, at some point you have to deal with environment variables, especially if you intend to do some development. I used to come from Open Source uX systems, and some old ones like HPUX, AIX, Solaris. When I switched to OS X, which is to some extent BSD - I had to find the best way to deal with env. variables. So - here are the ones that I use