Crush graham crackers in food processor.
Add melted butter and sugar and pulse to incorporate.
Press mixture into bottom an partially up the sides of a springform pan.
Refrigerate at least 30 minutes to firm.
In a large bowl, beat cream cheese and sugar until creamy.
Add in eggnog, rum extract, nutmeg and cinnamon. Beat until fully blended.
Whip heavy cream until stiff peaks form.
Fold eggnog mixture into whipped cream.
Spread evenly into crust.
Refrigerate at least 2-3 hours before serving.
Garnish with additional whipped topping if desired.