What do you use to write requirements and design software?

Question

Project management

Do you know any services for compiling technical specifications, designing a software product.
In fact, I want something that is installed on your hosting and used by the whole team for documentation, maintaining all sorts of documents.
Here's something like that, if you understand me.

Answer 1

jira + testlodge. If it is documentation - you can put a wiki.
The question is quite complicated, since many people understand different things by "documentation" and "requirements". I'm trying to write acceptance tests in Gerkin, and use it as documentation for the project.

Answer 2

TK in Word-e/Open Office. Interface design - it can be on paper, it can be an analogue of Balsamiq Mockups - there are many of them and they are free.
When developing software, the main thing is the version control system and the bug tracker. Recently, I prefer the Assembla system where it all comes together. Version control, bug tracker and Wiki.
But you can assemble such a system yourself from open source software products.

Answer 3

Google Docs + Axure RP 7.
Done, uploaded, posted a link, received feedback, corrected it, posted a link, and so on until the finish line.
Then you can export Google Doc to canonical Word, and from Axure cut screenshots for mocaps into tasks or pictures into TK.