Steins;Gate is a mind-bending anime which explores the repercussions of time travel. It has an amazing plot and some very likable and well-developed characters.
Another great aspect of the series is the quality of its English dub. I normally only watch the subbed versions of anime, and have been put off watching dubs in the past due to badly translated dialogue and poor voice acting, but Steins;Gate is an exception. The dialogue remains true to the original and the acting is fantastic.
Steins;Gate is definitely worth getting.