With the arrival of the first kid anticipated in June and the fact that I spent more this year that the entire rest of my life combined I'm probably done with purchasing gear of any significant price (i.e. Cost > $200) for a long time. This year my equipment expenditures were more than 95% of the total at around $6k. I doubt I'll exceed $500 in total next year, maybe a little more as I plan to get excellent tickets to a particular symphony performance.
A more interesting is what percentage of your income do you allot to audio related items in a year? I've never set any specific money aside for it, the agreement I generally have with my wife is we get to use any overtime cash on ourselves. My personal budget each month is $300, but that includes things ranging from playing golf to buying lunch at work. With my wife planning to cut back at work to about half time we'll be cutting back in a few areas.
Thankfully, I'm very satisfied with my current system and really don't have a significant want for any additional upgrades. But, there's always the list of things to dream about. In all honesty, the only big ticket item that really dream about would be a dedicated 2 channel integrated amp, possibly a Krell or Pathos.