Planning Tools
All sorts of planning spreadsheets - projects, parties, events, etc. Spreadsheets just work great for these tasks.
Enter and track all your guests and their kids. Calculate the total cost of the party depending on who's invited or who's coming. Keep track of all the things you need to buy or that people said they'd bring (for those more informal gatherings). Best part is collaborating with others in the plan - you and your spouse can update this at the same time and see who the other one already invited (whether you wanted them to or not!).
Create a Calendar on a spreadsheet! Just enter any month and year and this spreadsheet creates a calendar for you that can be printed or shared.
