Okay, I need to say something...You are all lazy bums, except for whomever asked the question. Don't just give a language that you like. Here, this will get you started. Go to www.libertybasic.com
and download LibertyBASIC. Learn LibertyBASIC(1/2 hr) and then go to http://www.leopardprogramming.com/source.php
and download the source code for a programming language created in BASIC. Take it apart, and add stuff that you like. That should get you started.