Volunteer work (I work with a therapeutic horseback riding group, husband works at the local library, we both work at a wildlife rehab group).
Work on art projects (currently building stuff for Halloween - we do a huge display every year, and I build props in specific themes, mostly using existing materials or stuff I pick up for free off of craigslist).
Catch up on movies/television/music.
Practice music (I sing with a parody group, husband plays an instrument).
Finding new recipes and cooking/baking. Planning the week's meals and then the shopping trips so I get the maximum amount of savings based off of sales and what I actually need and will use. (I love to cook, so I'm having lots of fun figuring out the best stuff for cheapest and then planning healthy and tasty food based off of what I can find).
Exploring local parks. There are a huge variety of county/state parks in my area. Even "pocket parks" that are under 2 acres. Most have at least a walking trail, but many have things like lakes, disc golf courses, mini golf (free usage of putters, balls and provide scorecards even!), nature trails, etc...
Learning to play tennis. We already had rackets and some balls and our neighborhood has courts. We're getting exercise, fresh air and getting pretty decent about getting the ball back and forth now, so it's getting quite fun.
Ride my bike.
Go to the gym and swim or work out on weights (we have a low cost gym membership).
Play games (board/video/computer). We just discovered we had a pack of Uno cards during a decluttering run.
Read. Love the local library!
House upkeep. Just cleaned and fixed the gutters, cleared some flower beds and dug out/created a few new ones, trimmed some shrubbery, treated the lawn for webworms (#@$!) and need to clean and refinish the deck either now or early spring. Also need to repaint a room and rearrange furniture, hang pictures, etc... never ending amount of stuff that isn't vital to do, so I get to it as I feel like it.
Go through things to reduce the clutter. Already gone through a large amount of clothing and donated TONS. Also took a hard run at our book library which took quite a bit of time but reduced it down significantly and made some $ in the process. Garage definitely needs a total empty and then going through. In the last week, just spent a few hours clearing some old bricks and building supplies that I will never use and took stuff over to the Habitat for Humanity's ReStore.
We also are planning on volunteering with Habitat for Humanity as soon as they have their next project neighborhood up and running - learning how to do house building stuff seems like a cool thing to do while helping others.