I was able to get the ByWater BASIC interpreter to compile under Linux with GCC. I had a bit of trouble and the MKDIR command won't work, but the rest seems to. I haven't tested it thoroughly, but so far it seems to work fine.
bwBASIC is an old interpreter, and it doesn't support all of the BASIC commands that we're used to. It might be fun to play with though.
Anyone interested let me know and I'll send you the tarball.