Steins;Gate is damn good scifi. It is thought provoking, has a great story, and has several interesting characters. And, to top it off, it uses my favourite scifi plot hook: time travel!
Unlike most time travel stories, Steins;Gate deals with the consequences (and moral dilemmas) of messing with time, even if it seems like the change is small. There is very little action and the plot is almost entirely dialogue driven.
I honestly disliked the main character, Okabe Rintarou, at the beginning of the series. The initial impression is one of a loud, maladjusted, and slightly obnoxious geek. However, as the story progressed and his true personality was revealed, I found myself liking the character more and more. It is great to see a geek in the role of the hero. We don't see that often enough in scifi, unfortunately.
But then again, the whole story exudes geekiness. A group of hackers (in the "maker" sense) led by Okabe stumble upon a method of non-physical time travel while working in their "lab", an apartment above a TV shop in Akihabara. As basic plot ideas go, it cannot get more geeky than that, can it?
Physical time travel does exist in the story, but is invented outside the scope of the series. This part of story draws heavily on the John Titor Internet meme from the early 2000s, just to complete the geek-out factor.
Watch this series. You won't regret it.