There is no doubt Portishead and Massive Attack are to be highlighted as some of the best bands from the Nineties, and as the most known acts from a mainly UK scene called Trip-hop.
Trip Hop was basically an experimental sounding leg of breakbeat with influences from soul, reggae/dub, ambiant, funk and jazz which occasionally made it into the charts with songs like Unfinished Sympathy (Massive Attack huge hit) or Glory Box.

In an interesting and frank interview, Geoff Barrows from Portishead answers questions about the band, the state of the trip hop scene, why Nineties bands are part of pop culture, or not, and an bold, but probably true, statement about why the music scenes don't glue together no more. Interesting, didn't we say ?

the interview http://www.spinner.com/2011/10/07/portishead-interview/
Portishead website http://www.portishead.co.uk/