Other bands like Massive Attack?

Not really, no. They're like Nine Inch Nails in that there are a lot of bands that you might like if you like them. But they're also completely different and unique in ways that don't apply to a lot of successful artists.

Someone mentioned Boards of Canada. If you like Massive Attack, you might also like them. They're great! But they don't sound like Massive Attack, imo. Best I can recommend is the first album by Sneaker Pimps. That also doesn't sound at all like Massive Attack. MA is just in their own league.

As a life long fan of Massive Attack, Im afraid I cannot tell you of any other band I found to match (matter of taste of course) but there are plenty good ones with a similar vibe

• Tricky (of course, ex member of massive Attack)
• IAMX (first few albums)
• Sneaker Pimps
• The thievery corporation (earlier stuff is more similar)
• Portishead (good but very very melancholic)
• Goldfrapp (early stuff)
• DJ shadow
• Yonderboi (all three albums are amazing, less electronic but he has a very special sound)
• Ancient Astronauts
• Nightmares on Wax

So, some of these would actually sound similar, many just give me the same vibe... As in, if you are playing a list of all those, it should more or less blend together...