What are the Special Gadget Combos?

I just noticed in the My Profile tab the Gadgets section of your stats lists "Special Gadget Combos found". It my swapping of equips to get Mix and Match I must have unlocked 11 of them.

What's a Special Gadget Combo and what ones are there? Do you get a special effect when using one or are they just gadgets that work well together?

The Special Gadget combos give a special title in the Gadgets section on the gadgets screen before you play again. Here are all 25 combos and titles I've found by trying all combinations. Please note that I've used the game's order of gadgets and avoided duplicates, because combo X + Y equals combo Y + X:

• Air Barrys &
  • Gravity Belt - High Mobility
  • X-Ray Specs - Futuristic Fashion
  • Ezy-Dodge Missiles - Air Dodger
• Nerd Repellent &
  • X-Ray Specs - Nothing to See Here
  • Free Ride - Disaster Averted
  • Flash - Not So Lonely
• Insta-Ball &
  • Gravity Belt - Serious Bounce
  • Freeze-o-Matic - Just a Little Further
  • Flying Pig - Fantastic Contraptions
• Gravity Belt - See above
• Missile Jammer &
  • Ezy-Dodge Missiles - Mild Missiles
  • Dezapinator - Quality Control
• Token Gift &
  • Magnetic Tokens - Spin Doctor
  • Free Ride - Instant Satisfaction
  • Lucky Last - Beat the House
• Freeze-o-Matic - See above
• X-Ray Specs &
  • Free Ride - Transport Tycoon
  • Lucky Last - Fortune Teller
• Gemology &
  • Flying Pig - Glazed Ham
  • Coin Magnet - Kaching
  • Flash - Petty Cash
• Ezy-Dodge Missiles &
  • Flying Pig - Miss Piggy
• Magnetic Tokens &
  • Coin Magnet - Magnetic Personality
  • Lucky Last - Great Odds
• Flying Pig &
  • Coin Magnet - Smash and Grab
  • Flash - Odd Couple
• Free Ride &
  • Turbo Boost - Speedy Steakfries
• Coin Magnet - See above
• Lucky Last - See above
• Flash - See above
• Dezapinator - See above
• Turbo Boost - See above