This excel sheet uses the Excel solver add-in to solve for the binary form of a positive integer value. I have not built it to handle negative numbers, but will do so with the next version I create. I will soon be posting a tutorial on each step necessary to build this type of analysis, which can be very useful for a wide variety of economic and managerial decisions.
Update - 07/29/13: Added an input box to allow the user to enter the number they choose into an input box rather than going into Data > Solver. The macro is setup to loop until the user chooses a number below 32,767 (the highest possible positive value for the integer data type). Once the condition is satisfied, the macro will run the Solver Solve function and a Solver dialog box will open with its results.
Let me know what you think in the comments section found here.