Many years ago my husband started this tradition for his nephews. Every Christmas and birthday he bought them a new tool. He started with the tool box and then filled it with tools. He kept a list for each one so he knew what they had and what they still needed. This is great for several reasons:
It takes all the stress out of trying to figure out what to get each time
He was able to watch sales and buy the tool sets throughout the year to save money
Each nephew has a complete set of really great tools to take with them when they move out.
My brother and sister-in-law has started the same tradition for my son. However, I use tools probably as much as my husband (my dad started my toolbox when I was younger as well) so we also had them start one for my daughter. We just store the toolbox on a shelf in their bedroom closet and then add the tools they get for each Christmas or birthday. My son already loves his and we actually used them the other day when we were putting a new bookshelf together in his room.