To me, a very interesting aspect of software is how some tools are used for purposes other than there typical.
In Support, we often re-purpose a tool in Revit to meet a need. Maybe that tool was intended for that use, maybe it wasn't, but we use that tool to meet our needs at the time. Think about using Walls instead of family components to design a kitchen as one example.
Clearly, this not the intended use the wall tool, but this is a unique way to solve a schematic design problem of laying out a kitchen and getting a rough view of what it might look like simply by creating a new profile for the counter top, applying it as a sweep (same for the toe space) and making the wall shorter (3 feet high in this case). This could save you some time trying to make all the cabinets fit into the space (when the cabinet guy is going to do that later anyway).
Another more complex example that I see a lot of is the use of the array tool. Array is not that complex a tool, but can be used for a lot of different purposes. You can use the radial array tool to simply array some chairs around a circle table for a furniture layout.
Or you can use the radial Array tool to array Model lines around a Arch.
Why would you do this though?
Well, functionality in Revit allows you to modify the rotation angle of a surface pattern (like making your wood floor go in a different direction) but its hard to make a surface pattern revolve around a circle, like bricks would around a arch opening.
To do this, you need to use the array tool and use it to create the look that you need.
If you want more information about how to create a Radial Array, the help file is great (insert common Support line here). Just search for Radial Array to find the information.
In this case, using Model lines to create the array allows the joint lines of the brick to appear in all view types. You could model this with component families or do any number of things to make the arch appear correct (drafting with detail lines for example), but in this example you can use a tool commonly used for one purpose to make your life a little easier.
What are some of the alternative uses of tools in Revit that you have come up with to do what you needed to do a little bit easier?