How to end a letter in Russian

[awelon.livejournal.com]

Hi everyone!
I'm going to be writing a card to a Russian friend soon, and it just occurred to me that I have no idea how to end it. All the phrases that I was taught in Russian class are quite formal and better suited to business letters. What are some common ways to finish letters between close-ish friends? In case it makes a difference, I'm female and it's to my male friend.

Thanks!