I've just installed abcjs
T:Speed the Plough
|:GABc dedB|dedB dedB|c2ec B2dB|c2A2A2BA|
|GABc dedB|dedB dedB|c2ec B2dB|A2F2G4:|
|:g2gf g2Bd|g2fe dBGB|c2ec B2dB|c2A2A2df|
|g2gfg2Bd|g2fe dBGB|c2ec B2dB|A2F2G4:|
The only restrictions are that the abc has to include an X: field (so that abcjs can recognise it) and that, due to a technical Microsoft restriction, Internet Explorer will not display the midi player (though it works just fine in FireFox).
Apart from that it works like magic.