In Naruto Shippuden: Ultimate Ninja Storm 2 for the PS3 and Xbox 360, you can unlock various Support Characters to play with just by gaining SP during your battles.
Support characters are free to choose between Attack, Defense, or Balanced support options.
Here is a list of the Support Characters you can unlock with SP, and how much SP it takes to unlock them:
Asuma – 660,000 SP
Chiyo – 680,000 SP
Deidara – 810,000 SP
Hidan – 840,000 SP
Itachi – 780,000 SP
Jiraiya – 690,000 SP
Jugo – 770,000 SP
Kabuto – 720,000 SP
Kakuzu – 860,000 SP
Karin – 750,000 SP
Killer Bee – 950,000 SP
Kisame – 800,000 SP
Konan – 890,000 SP
Lars – 990,000 SP
Minato – 970,000 SP
Naruto (Rasengan, Rasen Shuriken) – 620,000 SP
Naruto (Sage Mode) – 920,000 SP
Orochimaru – 710,000 SP
Pain – 900,000 SP
Sasori – 830,000 SP
Sasuke (Taka) – 930,000 SP
Sasuke (Kirin, Chidori) – 640,000 SP
Suigetsu – 740,000 SP
Tobi – 870,000 SP