Dragons' Den säsong 4

Students strip down; Kevin upgrades a travel website; the dragons get feisty over a business.

Twins present a line of lip gloss; a husband and wife duo; an eco-friendly clothing line.

A dance troupe shakes things up; an entrepreneur begs for cash; a tattoo business; lunchtime.

A casino dealer; a medical marijuana business; cell phone users.

Hopefuls try to turn dough into dollars; Arlene supports a bra business; Elvis impersonators.

A snowboard; an auto repair shop; table hockey.

What some of the most memorable entrepreneurs have been up to since their experience in the Den.

An offer makes fishermen greedy; DJ school; a fitness show for toddlers.

A sparkly swimsuit; a holistic healer; a Website that promotes recycling.

Diamonds made from an unlikely source; an underwear company; a board game.

A winter hat; futuristic living goes up in smoke; a familiar face braves the Den again.

A new tool; a top home designer is willing to put her name on the line.

A sauce business; a spray; a dress that provokes disagreement.

A computer mouse; a helmet for safety and style; a spa business.

A fruit basket; a revealing board game; an organic juice business.

A diaper delivery service; a scale; a boating business; a mailbox pitch.

The Dragons are treated to dessert; a condom that is safe for the environment; a board game.

The dragons go in on a million dollar offer; an eco-friendly business; a harness for puppies.

A rock business fighting the recession; a vodka business dances for dollars.

Defining moments in the lives of the Dragons.

Three of the best, brightest and greenest entrepreneurs present their business ideas.