I found the wintersowing forum on gardenweb in 2005 I think, and my gardening has never been the same since. When I found that I could save my own seeds, trade, get so many plants so easily, and essentialy for the price of potting mix, I was hooked. I'm cheap, no doubt about it. No expensive lights, no heat mats. Little effort on my part, and so rewarding. My garden became a constant work in progress. I grow hundreds and hundred of plants with so little effort, and I give away many more to friends than I can actually keep. If something doesn't perform in my yard, to the compost with it! I'll just grow some other seeds to replace it. I love seeing the whole circle of life- growing from seed, performing in the garden, and eventually composting and returning to the earth.
That said, I did invest in a few florescent lights and shelves for inside. There I mostly propagate coleus from cuttings over winter, and I do a few select seeds under lights in spring. My garden is pretty stuffed now, so I can't wintersow much anymore, but I will do a few milk jugs full of seeds. Winter and spring without wintersowing at all would be unthinkable.
But I realized this year that my garden was suffering from the seed starting mindset. I forced myself to spend a few dollars for great plants- something I was missing out on. I bought an echinacea Hot Papaya, Geranium Rozanne, Catmint Walkers' Low... a few others.
So I was a confirmed seed freak, but am slowly going through withdrawl and trying to find that happy medium between team seeds and team plants.