Write a napkin note: I was looking at a bike I want to buy, butt you were in the way. Sorry couldn't help it. Slap me on your way out if offended.

From below going up :P

Be specific about the reason you thank someone. Invent words or phrases showing you put some thought to make it funny.

For example, thanking about staying in someone's place as a guest.

''Thanks for...roofing me for the weekend :p ''

Finding common used words and expressions in people's vocabulary. Then repeating them on a daily base until they subconsciously stop  them.