Transparent Blurry Billboards for Mustang

A nice take on the transparent billboard variety: "Constructed from semi-transparent resin, the billboards accurately blur the scene behind them regardless of day, weather, or season."
-- Ian Hart

More transparency:
Transparent Billboard for DIY Stamps in Estonia
Transparent Billboards for Amnesty International
Transparent Billboard by Nike

A Whole Book of Cool Billboards and Guerrilla Stunts

If you like the stuff you see on Billboardom and Adverlab, you will love this book. Advertising is Dead - Long Live Advertising is a richly illustrated, annotated and cleverly categorized compendium of untraditional advertising approaches.

"Police Car Cutouts" Billboard

A very smart way to take advantage of a typical behavior: place a realistic-looking cut-out of a police car to slow the drivers down and read your billboard. This billboard for a Turkish bank reads, "Pay your traffic tickets on time without waiting in line - isbank.com.tr".
-- Frederik Samuel

Billboard and Photobooth Against Dandruff

Two brilliant ideas for anti-dandruff shampoos. The billboard has little transparent notes that you yourself remove from the hair. The photobooth tricks you into taking a photo of your scalp. Simply brilliant.
-- Coloribus

Giant Racket-Trampoline Promotes Tennis Cup

An installation in China to promote a tennis competition consists of a giant racket with trampoline functionality and a guy jumping up and down. The copy reads:
"The fastest server generate over 560 Newtons. Enough force to propel a human skywards.
Experience the best tennis at the tennis masters cup 2006".
-- via Ads of the World

"Wash Your Hands" Decal

Life sized decals placed on the doors on the way out of men's bathrooms around Toronto warn citizens about the dangers of germs and direct them to the washyourhands.tv website.
-- via Cool Hunter

Video: Melting Ice Moms Fight Smoking

Ice sculptures shaped like pregnant moms with a plastic baby inside where installed on the streets to melt. The point? "Over 30 million children lose their moms to tobacco every day." More at Trend Hunter.

keywords: billboard, outdoor, guerrilla

Nintendo DS Wrap on Tokyo Train

Actually, I'm not sure it's Tokyo, but it's definitely from Japan and it promotes Nintendo DS. It comes from Plastic Bamboo.

Tend-card With Homeless Kid

Tent-cards with a cut-out of a homeless kid were left on the restaurant tables around India.
-- via jwhx