When I was training in Maastricht, another mate of mine was working a position next to me....
Pilots had already all the time been requesting different levels than what they filed.
suddenly pilots comes in, was flying something like 330.
Pilot: "Maastricht, XYZ123 request higher"
mate: "Roger, XYZ123, What level would you like"
Pilot: "Euhm.... well any Level would do, just just would like to get anything higher if possible, XYZ123"
we all look at each other, immediatly thinking the same thing....
mate: "XYZ123, climb FL550"
everybody starts laughing like hell, other pilots also show their respect for this one on freq.
Pilot comes back also laughing out loud: "well euhm, thank you

, but euhm maybe we'll only start climbing FL370 for now if that's fine as well "
Sometimes the funniest things can be so obvious and sooo simple