Found the code via http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1267762668/9
Noticed it's not interrupt safe so did a quick-and-dirty sprinkling of volatile keywors and it happens to work
Also limited the FIFO size the 255 (uint8_t vs int, for strategic variables) to conserve memory. If you need larger buffers: define SIMPLEFIFO_LARGE before including SimpleFIFO.h which will use uint16_t for those variables.
See also http://code.google.com/p/alexanderbrevig/downloads/list