Chances are that your problem is not technical at all. Changes are that your problem is a human caused problem. You are not working together, not collaborating. Adding a tool will just mask the root cause. But most management will purchase such a tool if it has some good smoke and mirrow hand wavy justification.
My first recommendation is to use your brain. Then use your hands. Make your problems visible. Draw them on a white board, or a flip chart or an A3 sheet of paper (11x17 for you Americans). Yes use your spreadsheet to track trends and make graphs, but when the canned graphic routine doesn't draw trend lines, print it and use a pencil.
Because you click to see a list of tools here's a small list of tools you may find useful. Please help me add to the list - use the comment field below.
Innovation Games - the book and the online site has 12+ games to create delighted customers via games that get work done. Instant Play Games
Many teams use Dot Voting as a means of reaching consensus. Try the online site DotVoting.org to pre-arrange a vote and run a round of consensus making via a distribute online tool.
The artistic person will wish to summarize a feature and one way to do that is to make a word cloud of the requirements document. Try Wordle an online word cloud tool. Or try Tagxedo - allows uploading shape files.
"You never develop code without version control, why do you develop your database without it?" The tag line for LiquidBase a database version control tool.
Need a distributed team to work with story cards and a cork board for visualizing the relative effort of each story - try CardMeeting.com.
A similar tool used to create a story map is CardMapping site, see the usage of mapping stories article.
Basecamp is a project management system desing for online collaboration. It is integrated with 37Signals other online suite of tools.
Many Agile team's use timeboxes - for this one needs a timer: e.ggtimer.com/ is one option as well as Timer-Tab.com.
When distributed team's wish to know if the team members in the USA are awake - try What Time is it There?
A classic white board diagramming and collaboration tool: Cacoo.
Want to see if your documentation is truly readable (understandable) - try this site: Tests Document Readability.
List of Collaboration Tools
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