My brother coded up this little initiative tracker. You input the character or NPC name, their current initiative score, and their number of initiative passes and click "add". You can add as many people as you like. When you're ready to roll, just click the roll button and it rolls the initiative of each character you've inputted for you. You can remove passes from characters as they go.
It also has some regular text boxes next to each character so that you can make notes about damage and modifiers.
I input all my players right at the beginning of a session and then add NPCS when needed. It's pretty convenient.
Here is the thread.
Here is the tool: http://justsimplecode.com/files/initiative.html
You can right click the link to the tool and "save as" to keep it forever. It wont be hosted forever.