While you can find a treehouse to rent using Airbnb, they also have a mockup of one for their employees to chill in.

Last week’s Wall Street Journal had a story, The Perk Bubble Is Growing as Tech Booms Again, on how technology companies compete for employees by offering more and more extravagant perks.

“Here in the capital of the latest tech boom, engineers and product developers work late into the night creating the next big thing. But they take office culture just as seriously, fueling behavior that is reaching a level of froth not seen in a decade.

Some Web start-ups are partying like it’s 1999. Airbnb’s housewarming later this month is to include a visit by rapper and occasional tech investor M.C. Hammer. The party room at reviews site Yelp Inc. has three beer kegs with built-in iPads to offer information about what’s on tap. Last month, start-ups Peanut Labs Inc. and AdParlor Inc. sponsored the sold-out “Pirates of Silicon Valley Cruise,” a $600-per-person seafaring party.