Spend your votes freely, and just keep track of really impressive things you wish you could vote up more than once. After you've been voting for a year, you wouldn't want to see a list of everything you've ever voted. If you try to book-keep to that level, you'll never actually read the nodes or write any code. You already see the reputation of nodes you've written and nodes you've voted (up or down), but only as you read the nodes.