Paint

I feel the need to paint.  Sometimes I get this itch...

Oh, I don't mean paint a portrait... I'm no good at that, I just mean paint color on a wall; I'm a pro in that area.

So... here are my thoughts and if you have any feedback, I'd love your input or even thoughts.
In December we painted our kitchen a shade of Green that wasn't exactly what we wanted, but we've lived with it and while we still don't love it, we no longer hate it as much as we did.  We've also picked up a backsplash that we're hoping will help us like the kitchen more.

Seem like I'm off topic?  I'm not.

Turns out buying a gallon of paint for the little bit of wall we have in our kitchen was WAY TOO MUCH.  So we have almost a full gallon to use yet!  Oy vey.
I'm thinking it might make sense to somehow use it in our spare bedroom.  Right now that bedroom has had very little attention from me/us; the walls are pink and have been for the year and half we've lived there.  Here is a pic from when we first moved in:

So.. I'd really like to avoid painting the entire room that green (click through the link above to see the green) and leaving it all just ... green.  Being that we weren't crazy about it taking over our kitchen, I really don't want it taking over this room either - regardless of how much time we don't spend in that room.  So I'm thinking either some neat technique or maybe an accent wall in the green... the question then becomes what other colors(s) to use with it?  Keeping in mind it's a guest room, I want it to be welcoming yet colorful is okay in my book.
I'd like to avoid using gray or blue as those colors are already in rooms upstiars.

Any thoughts or input on what colors to match with that green ... or what/how to pain the room to use up some of that green and not make the room look exactly like our kitchen?