When I go by myself, I will splurge on staying longer and camp at Fort Wilderness. I stayed almost 2 weeks this past August when there was a decent "room" discount for annual passholders. I can fly round-trip for under $150 including luggage...food, palatial tent, extension cord to keep my electronics powered in my tent, lounge chair, etc. I hardly buy any food because most packaged food in the gift stores and carts is junk food and Disney has a policy that CMs are not generally allowed to bring QS food or drink to a table even for disabled guests (crutch user, solo traveler, inept at balancing a tray of food and drink on my head while crutching around). Sit-down meals are just way too big for me to eat an adult portion. I splurge a bit on souvenirs...I own 4 pairs of ears now and probably 6 or 7 mugs, plus collecting and trading pins. My favorite souvenirs are things like a plastic bulb cover from a MSEP float, bits of the paper fireworks casings from shows over the years, a coin from a bus driver that says "I was caught being good".
I've also splurged a few times and visited during Christmas and New Year's. The room prices are insane but the I love the special holiday fireworks, free Christmas parades, local carolers who sing at the deluxe resorts, and general holiday atmosphere. Splitting the cost with other adults brings the room cost down, though I tend to spend a lot more on food since they enjoy the restaurants.
Back when my legs worked properly, I would fly for under $100 with just a carry-on backpack for a quick RunDisney trip and combine staying in the cheapest value and sleeping at the airport. Disney races are expensive, but worth it and a great value IMO.