gpxmap is a Processing sketch/application that visualizes GPS traces in a pseudo-artistic way. Given a directory full of GPS traces in .gpx XML format, it will draw them on a canvas and let you zoom/pan around them all you want. With no map data getting in the way, it gives you a nice context-free look at where you've been. Left click to zoom in, right click to zoom out, and drag around to pan about.
Once you have a view of your data that you like, you can export the image as a raster PNG or a vector PDF. The PDFs look great hanging on the 'fridge, while the PNGs look great on web pages. Have a look at my page of GPS maps for some examples: http://www.wirelesscouch.net/gpsmaps/
I won't claim it is the nicest, most user-friendly toy ever, but it is released under the GPL. So if it doesn't do what you want, feel free to fix it. Or send me email - I might fix it myself.
Depends on https://github.com/RandomEtc/processing-gpx