Findings:

• Ice bucket challenge
• North Pole's Open Ice
• RSA Secret Key Challenge
• challenge
• Pepsi Challenge
• Challenge of the Future
• Real World Road Rules Challenge
• Challenge a stupid patent
• The Saltine Challenge
• 13 challenges for the 13th generation
• Nodeshell Challenge
• University Challenge
• Agnosticism is the greatest intellectual challenge
• Christian challenge
• The Cheap Beer Challenge
• Scrapheap Challenge
• Minerva challenges Arachne
• BT Global Challenge
• Front Page Challenge
• Simon Singh's Code Book Cipher Challenge Cracked
• The challenge we face
• Reading Between the Lines: Lessons from the SDMI Challenge
• 24 challenge
• Daz Doorstep Challenge
• voluntary challenges in Nethack and Slash'Em
• The Great E2 Fin de Siecle Fiction Challenge
• European Soccer Challenge
• The 2-sentence Fin de Siecle Fiction Challenge Entry
• Learning Machine Challenge
• The 1-sentence Fin de Siecle Fiction Challenge Entry
• Fiction challenge results
• Challenge of Nexar
• Triangle Challenge
• Triangle Challenge Solution
• The Long Island Challenge
• Fed Challenge
• ECCp-109 Challenge
• Challenge Coin
• Chip's Challenge
• Ferrari F355 Challenge
• American Solar Challenge
• Freedom's Challenge
• James Randi Paranormal Challenge
• Three Peaks Challenge
• BOC challenge
• Challenge for Change
• Full Metal Challenge
• Cheesily Cheerful Chart Challenge
• The Lyme Park Downhill Challenge
• Most Extreme Elimination Challenge
• E2verse Valentines Challenge (collaboration)
• challenge response
• F1 Career Challenge
• Secret Me-Meta-Node Challenge
• The 99p Challenge
• DARPA grand challenge
• Challenge everything
• E2verse previous challenge (collaboration)
• Ivan's challenge
• Three Pint Challenge
• The Mentos Challenge
• wertperch's nodeshell challenge (document)
• Puzzle Quest: Challenge of the Warlords
• The Stephen King Challenge
• Harry Potter Interactive DVD Game: Hogwarts Challenge
• Millennium Challenge 2002
• THE IRON NODER CHALLENGE
• The Notebook Challenge
• Clomid challenge
• THE IRON NODER CHALLENGE 2: ELECTRIC BOOGALOO
• The Nuzlocke challenge
• THE IRON NODER CHALLENGE 3: THIS TIME IT'S MARTENSITIC
• Secret Santa Summer Nodeshell Challenge 2011
• "So?" is a challenge
• THE IRON NODER CHALLENGE 4: FERRASSIC PARK
• The challenge of writing a meaningful free-form poem using only two letter words
• THE IRON NODER CHALLENGE 5: THE FERROUS FRONTIER
• Sahara's Math Challenge # 1
• Noah's Ark challenge
• a partner who challenges you
• THE IRON NODER CHALLENGE 6: RUST NEVER SLEEPS
• The 2013 IRON NODER CHALLENGE (document)
• THE IRON NODER CHALLENGE 7: NODE HARDER WITH A VENGEANCE
• Up for a challenge?
• THE IRON NODER CHALLENGE 8: RUST IS FOR THE WEAK
• THE IRON NODER CHALLENGE: 9 FAST 9 FERROUS
• October Skeleton Challenge
• THE IRON NODER CHALLENGE XII: WE'LL RUST WHEN WE'RE DEAD
• even if you fall from an impossible challenge,
• where you see mysteries, i see challenges
• "Age by age" reading challenge
• A Challenge is Issued
• Congratulations, you are about to experience a profound challenge
• Ice
• Vanilla Ice
• Ice cream
• Ice Ice Baby
• ice fishing
• Chubby Hubby Ice Cream
• Iced Tea
• Cool as Ice
• Long Island iced tea
• ice skating
• ice skates
• dry ice
• Ice Cube
• Ice Cream Koan
• Black ice
• Ice IX
• Iced Earth
• center ice
• Ice Tea mix
• Disney on Ice
• Fire and Ice
• Bay ice
• Iced
• Ice plant
• Water ice
• ice fog
• freeze-dried ice cream
• Eskimo ice cream
• White pepper ice cream
• Chewing on ice
• green tea ice cream
• Ice angel (user)
• Electric Iced Tea
• Ice Age
• ice core
• Coming Out of the Ice
• liquid nitrogen ice cream
• Ice Bay of Forochel
• recipe for ice
• Labatt Maximum Ice
• ice (user)
• on thin ice
• Phantom ice cream truck
• ice polishers
• Fat free ice cream
• Cookies and cream ice cream
• Garlic ice cream
• ice cream sandwich
• soft-serve ice cream
• Running for Ice Cream
• Artic Ice
• ice beer
• Does Satan play ice hockey?
• ice box
• Ice Storm
• Ghost Dog and the ice cream man
• Bar Ice
• Ice Cream, A Penny a Lump
• Granita de Limone (Sicilian Lemon Ice)
• Freudian slips at the ice skating rink
• Homemade ice cream
• Shuddering like ice has been dumped down your pants
• The Box Said 'Do NOT Open" But The Seal Was Already Broken
• Smart Ice
• Ice milk
• Iced Mocha Shake
• Iced Kukicha
• Molson Ice
• Break the ice
• ice cream, jello and root beer casserole
• microwaving ice cream
• Ice Hockey

If you Log in you could create a "2 On 2 Open Ice Challenge" node. If you don't already have an account, you can register here.