Getting out on cold days

I'm home with the boys two days a week and we really can't go a day without having some kind of activity planned. I could happily stay indoors all day when it's miserable out but unfortunately the boys aren't satisfied with crafty activities and even the toys they like have a time limit. So even when it's cold and wet we need to do something that's at least slightly stimulating and uses some of the energy that boys of 4 and nearly 2 have. If we haven't done anything by mid-afternoon, it all goes a bit crazy. 

I've found that it's hard to get inspired when looking out the window at full, dark clouds and gusty winds so I decided to write a list of (pretty standard) local activity options as a prompt. Sometimes these activities are very short and often the journey (walking/buggy) is just as important as the destination. So here is my list of 5 activities for cold days. I would love to hear if you had more ideas!

1. The library: We (fortunately) have two within walking distance of our house. There are a few story and rhyme sessions but these never seem to be at convenient times for us though both have great sections for kids and the boys enjoy finding new stories to read. 
2. The park: Sometimes you just have to layer up and go outdoors as uninviting as that might seem. (Promising myself coffee from my favourite local coffee shop en route is usually the inducement I need.) Often by the time we get to the park, maybe have a quick go on the swing, kick a few leaves and hit a few tree stumps with sticks, we've had enough outdoor time. 
3. Playdates: It really helps to have a local network of mums or dads who are either stay-at-home parents or work part-time/from home. Going to someone's house is a great way to spend a few hours and my boys definitely love it (equally, we love having people over too, and it works just as well to use up lots of energy.)
4. Playgroups: I prefer playdates, but playgroups are great from time-to-time (I really can't do more than one or two a month). So keep a list of times and local venues handy (the ones near us don't require booking, although I think some might.)
5. Lunch/coffee date: This one really depends on the ages of your children, but since H still naps at lunchtime and M doesn't (and H will happily sleep in the buggy), going out for lunch or even just a coffee is quite manageable and M really enjoys it as it's great one-on-one time. 

So tell me, what do you do with your kids when the weather is bad?