Load Arduino flash code from SD card I have an Arduino Uno. It doesn't have a lot of memory space, which is a bit of a nuisance. I was wondering:  Is it possible to load a text file from an SD card and compile it on the Arduino into code that the Arduino can use. I don't really care if it is slow or uses 99% of the memory space just to load on the code. If it is possible would this work: use bootup code to load a piece of code to Arduino, dispose of bootup code so there is more code, do what ever that code does, dispose of that code, load new code.
See topic #16812, “Load sketch code from SD Card”, in forum.arduino.cc, which explains how to replace the ordinary Arduino bootloader with one that can load programs from an SD card.

Also see Bootdrive loads Arduino sketches from SD card at dangerousprototypes.com, which gives different code to do the same thing.  It also mentions BootDrive for Arduino from baldwisdom.com.

Note, the program code that these loaders install into flash is already compiled, as opposed to being original C source code.  If you want to load source-level code into the Arduino, look for an interpreter / interpretive language to run on the Arduino.