BBC Micro

First, let's review about where BBC BASIC gained its foothold...

BBC BASIC

If you want to recreate the old school vibe, in the browser...

Or if you want to leverage BBC BASIC as it has evolved to work directly on modern hardware...

BBC BASIC: Richard Russell's BBC BASIC portal.
BBC BASIC for SDL 2.0: for Windows, Linux (86), MacOS, Raspberry Pi, Android and iOS. on GitHub
BBC BASIC "Console Mode"
QBASIC to BBC BASIC translator
BBC BASIC (Z80)
RISC OS Direct for Raspberry Pi: A RISC OS for Raspberry Pi image that has a particular emphasis on programing RISC OS and contains BBC BASIC 5/6 as well as many other programming languages pre-installed.
BASIC Tips & Tricks
Brandy: An interpreter for BBC Basic (or Basic V as it is sometimes referred) that runs under a variety of operating systems such as RISC OS, NetBSD, OpenBSD, reeBSD, Linux, Mac OSX, Amiga OS, DOS (extender) and Windows.
Napoleon Brandy Basic V Interpreter: Napoleon Brandy is development of David Daniels Brandy basic, an interpreter for BBC Basic (or Basic V), This project can not claim ANSI C compliance as Brandy Basic did, but supports Graphics for the platforms implemented. OS currently supported are Win32 and DOS. Currently a preview release as it is functionally incomplete.
Matrix Brandy BASIC VI: a multi-platform BBC BASIC VI interpreter with optional SDL graphics support, released under the GNU General Public License version 2+. It is a fork of David Daniels' Brandy BASIC, base-lined at version 1.20.1 from his Sourceforge release, which hasn't seen any updates since 2014.
bbasic: An interpreter for a subset of BBC BASIC II.
atom-language-bbcbasic: Atom grammar for the BBC Basic language.
Retrocoding fun with BBC BASIC
BBC Micro Screen Formats

BBC Micro Bot: Welcome to 8-bit cloud. Send a tweet to @bbcmicrobot and it will run it on a 1980s 8-bit computer emulation! Source (GitHub)
Fun with BBC Micro Bot