Desperate times at hotels call for desperate measures like offering hundreds of free rooms.

That’s what downtown L.A.’s Westin Bonaventure is doing. The hotel is giving away 200 free stays, 50 a week, through April 18.

Guests can go to a page on the hotel’s Web site each Tuesday and register for a free room. The first 45 people to reach the site via the Internet and the first five via Twitter will get rooms that usually go for as much as $250 a night. The Bonaventure is also offering discounts on room upgrades and at its restaurant.

Other hotels may not be giving away rooms for free, but many are chopping rates unusually deep. The Chamberlain West Hollywood is offering a rate of $165 for its Grand King Suites every weekend in April, almost half-price. W Hotel in Westwood is also offering 50 percent off a second night through September, and the Ambrose in Santa Monica is offering its customers a range of freebies, such as breakfast, taxi service, wireless Internet, parking and bicycle rentals.

Why? The Bonaventure’s managing director, Michael Czarcinski, said that with business down about 20 percent, management was willing to try anything.

“We know that some people will come for an extra night or eat at the restaurant, but the main thing was to really get visibility with the promotion,” he said. “The first week we had a few thousand hits on our Web page, and the second week we started getting phone calls from competitors asking, ‘What are you doing? You’re all over the Internet.'”