Hey I'm looking for a time travel manga/manhwa/anime.
What I want is something similar to Steins;Gate where the person travels back to the past but they know how events unfold so they take advantage of it. It can be a few days or centuries in the past as long as the MC isn't an idiot lost in time.
The MC should know where he/she is and what happened historically and use their modern-day knowledge to show-off/succeed etc...

As for the genre I'm ok with anything except yaoi and hentai. I prefer shounen/seinen but I'll accept shoujo/josei too.

Zipang fit's this description but I'm not sure if you're looking for this kind of series/genre...

It's kind of a spoiler so here you go...

The anime Darker than Black has something like that somewhere near the end.

Edit : SO, there are two other great manga/anime that fit (imo) but it's also inevitably spoiler (for both). Do you want to know anyway? 😕

the third story from 100% Gokuama Kareshi! - a bittersweet shoujo oneshot
Black Cat Tunnel
there is an arc on time travel in Kateikyoushi Hitman Reborn!

but the characters go to the future though...

or you could try Arcana 11: Time Travel & Time Travelers

Ryuurouden

Help! I'm looking for... manga with dangerous guys [url]http://www.mangaupdates.com/showtopic.php?tid=39874&page=1#post594033[/url]

Quote from Pebble_

It's kind of a spoiler so here you go...

The anime Darker than Black has something like that somewhere near the end.

Edit : SO, there are two other great manga/anime that fit (imo) but it's also inevitably spoiler (for both). Do you want to know anyway? 😕

Does that mean the time-travel portion is only a small part of the story?
I wouldn't mind trying them but I would prefer that the time-traveling is a major part of the story.

Quote from Contently

Does that mean the time-travel portion is only a small part of the story?
I wouldn't mind trying them but I would prefer that the time-traveling is a major part of the story.

Mmm I'm pretty sure I know one of the manga Pebble_ wants to recommend, and the problem is that you're not aware there a character not belonging to that time, so you don't know there is time travel going on.

Beside that one, my two cents:
Dna2
Noein (anime)
Suzumiya Haruhi no Yuuutsu
Actually they're all people coming to present from the future, is that still ok?
Also Threads of Time is kind of what you asked, but not a favorite manga of mine. And Thermae Romae too.

Did you already check the time travel/time manipulation categories? There is quite a lot of stuff there.

What I like in Trivial Pursuit style. Pick your category:[img]http://i379.photobucket.com/albums/oo233/Reid4891/Manga/trivia-1.jpg[/img]

Sengoku Strays

[color=green]"Officially, this machine doesn't exist, you didn't get it from me,
and I don't know you. Make sure it doesn't leave the building."[/color]

Gyakusou Shoujo mm kinda fits also Ever 17 but i recommend reading the visual novel not the manga..

well Threads of Time is not a favourite of reid1 but one of mine so I'm seconding it ^^
there is also Mirai no Football a really nice and unique piece ^^
and maybe Anatolia Story it's shoujo but hase some action and a likable female protagonist ^^

Time Eliminator works. There aren't many chapters out though (maybe 2-3) but the story and art so far are quite good.

Tesla: If an immortal vampire dies in a virtual world-

Magnus: -does he make a sound?

Likes: Action, adventure, drama, fantasy, historical, horror, mystery, psychological, sci-fi, seinen, shounen, supernatural, tragedy

...I read too much >.>

Quote from reid1

Mmm I'm pretty sure I know one of the manga Pebble_ wants to recommend, and the problem is that you're not aware there a character not belonging to that time, so you don't know there is time travel going on.

Yep, so it's a major plot point as well as a spoiler.

Same problem with the other one, though this one is a bit more far-fetched for a suggestion of 'time-travel'.

First one is the anime Puella Magi Madoka Magica in which one of the characters keeps re-living the same events, in an attempt to change the outcome.

And the Higurashi series are based on the same "relive events to change outcome" twist, except there's no time travel. Instead, there is one character who goes from one alternate universe to the next.