Dude.

Dude! *nods*

I've always loved that word. Makes me think of a young, stoned surfer without too much of a brain. Preferably with an Australian accent.

There's a commedian who has a bit in a routine about the word "dude"  He claims the it is the only word you need, because it can mean anything based on how you say it
(this won't translate well on paper, but...)

How's it going? -- Dude.?
Check her out! -- Duude!!
is an ax murderer in the closet? -- ...dude?

Dag is another good word for many uses, though not as widely applied.

dued?

*g*

To just be incredibly silly: Doed! (Dude with a southern accent :) )

Oh, not that again. You'll get everyone talking in that funky language I don't understand. (And, of course, that includes all languages. *grins and ducks*)

duuuuuuuuude....

dud

oops

Ah, but can the umlaut contend with the schwa?

schwa this!