Excel-Like Spreadsheets
Originally, when planning this product, we thought we'd follow Microsoft's lead and develop something that worked like Microsoft Project, but then everyone we talked to told us how much they hate entering data into Microsoft Project.
The solution? We created a spreadsheet-style "grid entry" that's a pleasure to use.

How to use it
Just flip to the "Project" grid and you can enter all your project data as easily as if you typed it into Excel.
Cells containing functions show up with a red square in their right hand corner. Click the red square to see/edit the formula.
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Any data you can find on a grid in this system (project information, resource information, costing information, etc..) can then be used in your own formulas.

We then completely re-invented the way that projects are managed and gave you 13 other grids to play with that you can use to create any type of report you can imagine for project planning.
Now admittedly, this is NOT Excel and you'll see that there are many features we are missing that Excel has.
That said, you'll find 108 of the most-commonly used functions in Excel.