There's iWork and Google Docs. There's also Open Source projects, but don't lose your time with that, you'll be deceived.
GOOGLE DOCS : Feels like you're opening Office 2003 in your browser. However, it integrates a few Cloud features and a few other "later versions of Office" features. In fact, it probably offers the best collaborative tools out there. But your data is on Google's. And its look and feel is completely from the past.
IWORK : Keynote is better than Powerpoint, but not by a lot. The magic tool to make backgrounds transparent on pictures is probably its killer feature. The interface is also pretty convenient for animations, and speaking of animations, their quality exceeds Powerpoint's by far.
Pages and Numbers though, beware about them if you're a power user. They are too simplistic and do not offer enough advanced user features (i.e. the lack of Pivot Tables after so much time is killing me, especially since I learned it existed on the Mac more than 20 years ago). If you're running a large business, this can't be a choice to consider.
BOTTOM LINE : I'll be completely honest, every time I try something different, I go back to Office. And yes, I am anti-Microsoft. But that Ribbon interface, when you find yourself lost and swimming through all the features these apps contain, is a complete killer that no other app rivals. Plus, it has the most advanced features an Office suite has ever contained.
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Apples suite of productivity apps are terrible, the fact it depends on the joke that is iCloud is why it won't ever be good
Just to make things clear : It doesn't.