Yesterday there was an article in the New York Times entitled In New York, Power of DNA Spurs Calls to Abolish Statute of Limitations for Rape (registration required). As the title suggests, the article discusses the movement to elevate rape from a Class B felony with a statute of limitations of 5 years (or 10 years if the perpetrator's whereabouts are unknown) to a Class A felony, which has no statute of limitations.
Although I'm a former Assistant Public Defender and generally view criminal issues from a very defense-oriented perspective, I'm 100% in favor of that proposition. While I can understand the concern that the police may not be as motivated to promptly investigate a rape if the statute of limitations is abolished, I think that it is outweighed by the extreme injustice that occurs when a rapist is allowed to roam the streets in search of additional victims in spite of a positive DNA match. (I cringe when I read my prior statement, since it sounds oh-so-prosecutorial, but that's my perspective on this issue, nonetheless.)