I organize my photos in a couple different ways.
Like you, most of my photos are organized into folders. My primary sub-folders are listed by year. Everything captured within that certain year will be in the folder with that year on it. Within the yearly folders are other folders, organized by type (family, animals, weather, food/work, etc.).
Have you noticed that Windows automatically alphabetizes photos in an ascending pattern?
When I was heavy into metal detecting, I usually took photos of the things I found. I would name the photo starting with the date in yyyymmdditemdescription.jpg format. Basically, that was the date I took it, year first, month, day, then a one- or two-word description of the item. So, hypothetically, if I had found a silver dime today, the name of that pic would be 20090128silverdime.jpg. I wouldn't have to look very hard to find it, as it would be at the tail end of the files listed in that folder.
I do something similar when I name the pics of food at work. It starts with the year, but then is called an "app" or "entree". If it's a special item, I'll put the word "Special" between the year and the "app" or "entree". After those, I'll give a one- or two-word description. I ran a special tonight of some Chicken Marsala. If I had taken a pic of it, it would be listed at 2009SpecialEntreeChickenMarsala.jpg.
Hopefully this will give you some tips that you can use.
Peace, Love, and Vegetable Rights!
Eat Meat and Save the Plants!