I finished up my phd a few months ago, and was accepted in a very competitive lab in the USA. I should be grateful, it's the perfect topic in an amazing city. However, after ~6 months I feel burned out. I've been given ~7 projects, plus supervising undergrads, and I've been working 15-16h a day for a few weeks now, from 9am to 12am/1am. I have to come in on Sat and Sun also for a couple of hours to monitor rodents. This week no experiments worked and I have to make some powerpoint slides for the weekly lab meeting tomorrow morning. I feel lifeless and barely recognize myself in the mirror anymore.
On the bright side I got an Ipad 3G before all you guys back in the UK. :p Yes, it's awesome for reading papers and I likely won't be printing a paper again.