This project was really just a great reminder of how complex creating a typeface would be. I used Inkscape and followed some of the advice in this article. My process was pretty simple. I sketched the icons out on paper and took photos of them with my iPhone since I didn't have a scanner around.
First I worked on the photos by opening them in PhotoShop and adjusting the brightness and contrast. I saved and opened them in Illustrator where I Image Traced them to create a vector version. Then I opened each one in Inkscape where I sized and aligned them on the baseline and assigned each one a letter on the keyboard.
If you'd like to use it for your own projects, feel free to download the .ttf.