Contemporary Strings aren't very popular... This is the list they gave me. I hope I got the right links.

• J. S. Bach (D): contrapunctus XIV (arr. for string Quartet by P. Higgings)
  • http://youtu.be/JbM3VTIvOBk
• Benjamin Britten (UK) : String Quartet N. 3
  • http://www.youtube.com/watch?v=TR00rQDB6Sk&feature=share&list=PLD05629B3E8DE938C
• Anton Webern(AUT): 6 Bagatelles
  • http://youtu.be/yEcVQH_sC3s
• Alex Mincek (US) : String Quartet N. 3
  • http://youtu.be/EjTQZhMn8Wg
  • http://youtu.be/wUGOgFCRolQ
• Ashley Wang(TW/US): Retrogradable Dilution
  • http://www.ashleywang.com/resources/Retraogradable+Dilution.mp3