This isn't exactly a powerful computer but it does have a real BASIC interpreter. I bought it for $5 with some non-working keys and a dodgy LCD but some Deoxit and a couple of bodge wires fixed it right up.
@Cloudscout These things piss me off so much -- they wasted so much potential. Would it have killed them to include composite monochrome output, a serial port, and some GPIO?
@mos_8502 There are some bus connectors intended for memory expansion and ROM carts. An audio jack for saving/loading tape files, too. If I was smarter, I'd try to hack something on it.