With some inspiration gained from other similar projects posted on the Internet, I turned a Sony Walkman cassette player/recorder into a guitar amplifier run on 2 AA batteries.
Step 1: What you will need
Here is a list of the items you will need to make the amp:
1. A cassette player with a speaker (Preferably also with an equalizer so you can change the sound settings just like on a real amp).
2. A regular instrument cable.
3. A wire cutter/stripper ( I used a fruit cutter knife :P)
4. A Solderer.
5. Rosin-Core Solder.