Nice!

I haven't, but it's something I thought about this past year and am deciding to start incorporating that word and others.

It's just a way to express that you like something or think something's cool.

"This song is groovy"

Someone hands you a soda "groovy my dude". It's just like saying "sick" or "sweet"

If you've ever seen evil dead 2 or Army of Darkness, see how Ash (Bruce Campbell) uses it.

https://www.youtube.com/watch?v=YtyU2PJCk7Y

Depending on the circumstances, you can't avoid speaking to some people.