In the age of instant tweets and impulsive Facebook posts, some companies are still trying to figure out how they can limit what their employees say about work online without running afoul of the law, the Associated Press reports. Confusion about what workers can or can’t post has led to a surge of more than 100 complaints at the National Labor Relations Board — most within the past year — and created uncertainty for businesses about how far their social media policies can go. “Employers are struggling to figure out what the right policies are and what they should do when these cases arise,” said Michael Eastman, labor law policy director at the U.S. Chamber of Commerce…