Last month, Representative Anthony Weiner released a report showing that 85% of registered sex offenders live within 5 blocks of NYC schools (here's a PDF of the report). Included in the report was a map illustrating this point; the report says, "Cartographers at the Library of Congress have plotted the location of every school and every sex offender in New York City on a map. Every sex offender is represented by a red dot, every school is a blue building on the following page."
Weiner has a few other recommendations, including establishing a federal grant for sex offender monitoring, tracking sex offenders within 2 blocks of school with GPS, and creating a national task force to reduce sex offenses. Weiner and a bipartisan group from Congress (including Senator Schumer and McCain), announced the KIDS (Keeping the Internet Devoid of Sexual Predators) Act of 2007, which would "require sex offenders to register their e-mail and instant message addresses with the National Sex Offender Registry."