The first one that comes to mind is Erebus which is a webcomic following a conflict between brothers fighting for a throne, that causes a war of sorts. It's sci-fi and very very pretty. I highly recommend it.
Also Griefer Belt which I've been reading for almost a year at this point. It's about a bunch of people working for the black market. It trends almost constantly though, so I'd be shocked if you hadn't seen it around at some point. Haha. (I mean, the artist also did art for the site...so) either way, I highly recommend it still. It's a great read.
And last but not least Flowerpot. It's mostly a slice of life about a group of people that have flowers grow on them. It has a bit heavier romance than the other two I've mentioned, but it's very story line driven and has great characters that it follows often. This is another that trends fairly often, but I can't stress enough how much it deserves to do so.