Luxembourg (aka "the bourg", "Lux" or even Luxoland) might not be big in size but it definitly has some festivals worth mentioning!
Every summer this little country turns into a party central and attracks lots and lots of people from our neighbouring countries.

RockAfield(http://www.atelier.lu/raf/): This one day festival has already attracted a whole bunch of famous artists and bands from the rock industry such as The Kooks, The Verve, Mando Diao, The Killers, Queens Of The Stone Age, The Hives, Billy Talent, Placebo, Franz Ferdinand and Muse.
Long list right? Obviously you won't get all of them together at the same festival but this gives you a pretty good idea of the kind of bands playing there.

Jazz&Blues Raly: Blues n' Jazz Rallye(http://www.bluesjazzrallye.lu/): This one day totally FREE festival happening in the old town of Luxembourg city is dedicated to jazz and blues as the name says, so for all those lovers of good music don't miss out on this great opportunity to listen to big names such as Joey Defrancesco, Alphonse Mouzon, Larry Coryell, Sean Carney band and much more!

These are just two examples of festivals in Luxembourg, many more happen every year.
Also with the construction of two brand new music halls, a lot of musicians are finally visiting luxembourg. For more information visit: http://www.rockhal.lu/ and www.philharmonie.lu

Last but not least, this small venue is ideal to get as close as you will ever be to your favourite bands: www.atelier.lu
Every once and a while bands such as the artic monkeys or Eagles of Death Metal visit the atelier and rock your world!