Here's my favorite option for backcountry fishing. It takes a pen fishing rod, and replaces some parts to fit spincast reels. The spin casting reels are easy to use, and good for learning to cast.
Pen Rod - I've been using the rods from GoFastAndLight.com (I've received great service from them). If you're outside the US just search for "Pen Fishing Rod" and you should find other sellers. Some of the other rods out there are lower quality though and may not work as well.
Here are the reel options:
Shakespeare Synergy Microcast - This one is nice and compact. I've found it helps to remove some extra line on the spool to avoid tangling and jamming.
Daiwa Underspin US XD 40 - Bulkier than the Synergy reel, but is more comfortable to use for longer periods.
Zebco 11 Micro - Similar to the Synergy Reel, but I haven't tried it yet.
Fly Reel - For fly fishing, haven't tried it yet.
*some of the handles in the pictures have been covered in 1" heat shrink tubing to improve strength and grip..
1 Buy a pen fishing rod and take it apart (you will need the rod part and the knurled nut).
2 Print out "Test Thread.stl" and check the fit with the threading on the handle side (not the front thread). It should be tight, adjust scale if necessary.
3 Get one of the reels in the pictures.
4 Print out the parts associated with the reel (handle, nut, and cap). Make sure the parts are oriented correctly, no support structure should be needed. If it's necessary adjust the scale to fit.
5 Replace the original handle and washer with the printed handle and use the printed and knurled nuts to hold the reel in place (see pictures). Use the cap for storage / travel.
Post a picture of your rod with a fish you caught with it in the made section.