Do something that has no relation whatsoever to design. Seriously.

I feel my most creative on Monday mornings (seriously) after I've taken 2 days off to have some beers with friends and just do something mindless like watch a Law and Order marathons. ;)

When you live, eat, breathe, and sleep design, doing something completely different and almost mind-numbing can be beneficial (for me at least).

I find watching videos from design conferences really inspiring. Not so much the technical ones, but the ones that address the larger issues around design. Both Webstock and XOXO had some good ones this year. You can watch them here and here.

Mary jane.

Gaming, watching movies, tv shows (Breaking Bad...bitch), going out nearly every day and meeting friends you don't see often is my way of getting back into it.

Adrenaline. Go ride your bike or do something that scares you.

Lots of great suggestions here. I agree with getting out of your comfort zone and doing something creative that's not digital (get your hands dirty!).

I personally find that lots of breaks and working the left side of my brain works well. I work in 35 minute Pomodoro sessions, with a 10 minute break in between, and in that 10 minutes I solve a Rubik's Cube twice (or more if I'm warmed up). This helps my creative side rest while I'm using my logic side for a bit.

As a developer, this happens to me as well. I typically go back and forth between excessively gaming and excessively working on open-source projects. I've been trying to find a better middle ground but it's harder than it sounds. So easy to get pulled into something and then get burned out on it.

Plenty of great comments here. I think a lot of them can be summarized by "getting out of your comfort zone". This doesn't mean that you have to do something you don't really feel like; it means doing something you're not used to. This can be as little as swapping to a different playlist/radio channel on Spotify, or as big as emigration, but my guess is that you're somewhere in between.

If these things don't help, talk to others. Maybe you have a colleague you can confide in. This is something that has helped me, because generally when you get into such droughts, it gets noticed by others, and if you don't talk about you seem like someone who doesn't care. This can create a really bad vibe, and put you into a vicious circle where you try to hide your inactivity/lack-of-inspiration, causing your colleagues/superiors to become suspicious, which in turn will make you feel worse about not feeling good.

So I'd say, talk, and try and evoke change.

I would change habits, if you are in a rut at work then change your job/team/project.

I agree with what else has been said, exercise - try new food - sketching more - even try something completely new (photography, car racing, take a flying lesson - what ever you like).

Go explore, shake shit up a little.

Interestingly enough, I rarely get in a creative rut but I do fight the lazy version of myself that settles with mediocrity. Laziness is my mortal enemy.

This monday one of the Design&Banter event talks was about this (more or less). Hannah Donovan from ThisIsMyJam did a short version of this talk: http://www.youtube.com/watch?v=qaLcnzs1hcI

Pretty inspiring and great tips of how to get rid of a creative block or a burnout.

Thank you everyone, these suggestions really help. I think I might take a week vacation and do some things I'm not use to doing. That might really help me get back on track.

Kyle, I'm in exactly the same boat, and I'd love to get some similar tips/ideas to get out of my own rut as well!

I would have to agree with Sean though, that changing some of your habits is probably as good a place as any to start. I know I definitely need to get more sleep at night, as it's probably a good reason behind my lack of focus during the day.