I played the violin for 10 years currently. Just finished my Grade 8 examination and still waiting for the results.
Wish me luck!

Ooh, what did you play for it? Was it with ABRSM?
Kisarou, what exactly are grades and examinations? (In terms of violins o.O)
It's the same in terms of (almost) any instrument. There are various musical exam boards, the most well known of which is ABRSM (Associated Board of the Royal Schools of Music). They offer practical exams in most standard western instruments, graded 1-8. With ABRSM, you have to learn 3 pieces, do a few technical exercises (scales and arpeggios), some appropriate level sight reading and then some quick aural tests that are standardised across instruments.
Only instrument I can think of that is noticeably difficult is Voice, where you have to learn 4 pieces and tech work is replaced with an unaccompanied folk song.
Once you've taken grade 8, there are 3 levels of 3 Diplomas, Music Performance, Music Direction and Instrumental/Vocal Teaching. Within these you can take DipABRSM, LRSM and FRSM exams which are much harder than grades 1-8 and set out differently.
DipABRSM for Performance for example, you have to play a 35 minute recital. You get a list of advised repertoire but you're allowed to choose other works as long as they're the appropriate standard. You then have to write 1000-1200 words of programme notes on your recital, undergo a 10 minute Viva Voce as well as a Quick Study (bit like the sight reading in earlier grades).