Actually... contrary to what I thought due to not using BASIC for so long, it seems BASIC can still be useful - I just took a cursory glance at
BlitzMAX (60€),
DarkBasic (?€)and
PlayBasic (learning edition:free; pro 15€?) developing environments (which, unless I misunderstood something, are connected to BASIC) and they all look interesting and relatively alive.
The few BlitzMax-developed games I played were really smooth and felt solid, and it even has a very nice 3rd party IDE (the one I played with is free for lite, 75€ for full version). DarkBasic I didn't like that much mostly because I got the impression the guys that are selling it are scattered all over the place and there were too many things I wasn't interested on their site (3d stuff primarily). Also the DarkBasic games I played were a bit glitchy and one of them bluescreened my computer so I'm not interested in it anymore. Maybe I was just unlucky. PlayBasic is by far the least popular (their last competition attracted... two games) despite being the cheapest but it feels fast and simple. Looks like it doesn't have that many playable examples though.
Seems the guy behind BlitzMAX recently also wrote something called "Monkey" which is supposed to be similar to BlitzMAX but with the ability to export to all kinds of platforms (among others - html5, flash). Interesting stuff.
Edit: there's a site about various (mostly alive) Basics here:
http://www.basic.mindteq.com/index.php? ... &Itemid=56