Its a heatmap! *crowd oohs and aahs*
Have you ever sat down for a bit with Google Maps and gazed at all the places you've been, for old times sake? I rarely reflect on my past, but this is an exception. So, go browse some of the places I care about
So how is it done?
If you try searching "Google Maps Heatmap", the first few results instantly hit you with code, which some may be familiar with (HTML and JS). Really though, this isn't very friendly to make yourself a little heatmap, is it? Another option is to follow the friendly, guiding hand of Open Heat Map, which will ask you to upload a spreadsheet of every location point.
Now I'll be honest, I tried both approaches, and neither was quicker. See, to get the data for your heatmap, you still need to locate each individual point before then converting it to JSON, or chucking it in a spreadsheet.
It does look good though, right?