First post!
My wife and I (from Montreal) manage to hit WDW every year for about 3 weeks. Our trips cost around $5000. Although this is a big amount, it could be worse for 3 weeks on Disney property. I assume most of you are already aware of the "tricks" we use, but here goes anyway ...
We always stay at the value resorts (AS Sports, Music or Movies) and arrive on a "value season" day. As most of you know, even if part of your trip runs over a holiday, you still pay the value rate for the room the entire stay. With the Disney Club card, the Annual Pass or some discount code, we haven't paid the rack rate on a room in several years. For instance, we are heading down the first week of September and got the great price of $49 US at AS Sports with a discount code listed on MouseSavers.com (this was before the code exclusively for Canadians was advertised).
We purchase an Annual Pass and schedule our trips to use the passes twice. For example, we go in early February one year, and in mid-January the next year using the same Annual Pass. In the past, we usually renewed our Annual Passes to save a bit of $. However, Annual Passes now activate on the renew date, so we will no longer be renewing them.
We joined the Magic Kingdom Gold Card Club several years ago, now it's just called the Disney Club. With this card, we save about $20 US (?) on the purchase of each Annual Pass, so it pretty much pays for itself right off the bat. Other small savings with this card add up. Plus, it's great to get the Disney Magazine in the mail!
We do not rent a car. We usually go off site only a few days (like for a day at Universal Studios), and we simply use a Taxi service or Mears.
We buy and use the refillable mugs at our Resort! We usually hit our Resort for lunch (mid-day break), so the mugs are really (I mean really) used over a 3-week period.
All our souvenir purchases (usually not very much) are made at Downtown Disney using the American Express credit card. Thus, relatively the same souvenirs from the parks cost %15 less (I believe total amount must be over $50 for the discount to apply).
We have a very good
travel agent (I think

. I do not recall ever paying more than $400 for our plane tickets from Montreal to Orlando. With Canada 3000, the current rate is $299 (including regular taxes) for a direct flight.
If you use a service like Tiffany Towncar to get from the airport to your Resort, they will let you stop at a grocery store to pick up a few bags of food. Considering the price of some basic stuff at Disney compared to what you pay off-site in a grocery store, I think this speaks for itself.
I am surely forgetting some stuff, but that's the main of it.
Regards,
Bobster.