QBASIC-like interpreters, implemented in Basic
bintqb.bas is the QB64 version
bintfb.bas is the FreeBasic version
Both interpret a QBASIC subset.
Note that these are pure interpreters - they don't tokenize and/or create any intermediate representation. They just interpret the source as is.
bintqb running a Tiny Basic interpreter, that is itself written in GW-Basic:
Same, and now loading and running Tiny Star Trek into gw, who is being interpreted by bintqb: