The Postal Service has self-service kiosks in more than 2,300 locations across the nation, and in a pilot program, several locations introduced a new generation of kiosks in 2013. Now, if customers enter these Post Offices and find the line is long or the counter is closed, they can use the kiosks to buy stamps, ship packages and send mail. The machines are easy to use and feature bright, larger touch screens, a scanner for pricing greeting cards and a scale to weigh packages.