Hanson

Zac Hanson -- the drummer from Hanson -- was the victim in a disgusting spit attack on his tour bus in Seattle last night ... and the gross moment was all caught on video.

Here's what we know -- the spitter somehow got onto Hanson's tour bus ... and as Zac was trying to boot him from the bus, the guy unleashed a big nasty loogie that hits Zac right in the head.

You can see the spit dripping off Zac's hair ... it's really disgusting ... but Zac simply brushed off the incident, and smiled as if it was no big deal.

As for the douche bag ... he simply turns and walks away while cursing out some of the people surrounding the bus.

After the incident, Zac tweeted ... "Gonna be a good show tonight, I cleaned off all the spit and I am feeling ready to go! -Z"

Still looking for that elusive follow-up hit to the ‘90s smash single “MMMBop” -- former boy band Hanson is now turning to booze … in the form of a new beer they’re calling “MMMHop” … this according to drummer Zac.

According to reports, Zac made the announcement during an event at Oxford University this week … telling the crowd, “We are soon going to be selling our own beer … I’m not joking – MMMhop IPA anyone?”

Through a rep, Zac tells TMZ, "Yes a branded HANSON IPA beer concept is in the works under the moniker 'MmmHops.' We're glad to see a bit of buzz around the idea, which has been brewing for some time."

In the meantime, it's been 14 years since MMMBop came out -- feel old yet?

For Sale: The Oklahoma mansion where the Hanson bros grew up and recorded one of their albums.

The Deets: Custom recording studio, 6 bedrooms, 5 baths luxury pool and cabana house.

According to TulsaWorld.com, the Hanson family bought the place AFTER the band achieved "commercial success" ... but Zac, Isaac and Taylor basically grew up on the property.

The fam has since moved out of the home -- but whoever buys the pad will get to use the state of the art recording studio ... where Hanson recorded their 2010 album, "Shout It Out."

Question is ...