Out of Office - Career Limiting or Career Break Through?

Most of us dream about taking a career break (After reading Eat Prey Love, it was all I could do not to run off to Italy that very moment!), but few actually do it. The number of people taking lengthy sabbaticals even at senior levels of their career is increasing. In part that's due employers coming to terms with the higher rate people change jobs; millennials itchy travel feet; and the need to retain top talent. Interested to hear from Procurious members who have taken a career break - What did you do (travel? Study? Family? Illness?)? What did you fear the most about taking a break? Do you regret it? Were there any surprising benefits to come out of it?