I encourage Ph.D. students to seek opportunities of Microsoft Research internships. I myself was interning here in the summers of 2003 and 2004. MSR internship is interesting, challenging and rewarding. Please ask your advisor to write a reference letter for you as early as you can! Most offers are made in the early spring.
Summer 2013: Eric Chen (CMU), expertise: web security. Welcome Eric!
Summer 2012: Yuchen Zhou (University of Virginia), expertise: web security. Project: Explicating SDKs, to appear in USENIX Security Symposium 2013.
Summer 2008: Hong Chen (Purdue), expertise: access control. Project: Browser’s residue objects, in EuroSys 2010.
Summer 2007: Ziqing Mao (Purdue), expertise: access control. Project: Pretty-Bad-Proxy, in IEEE Symposium on Security and Privacy 2009.