The SparkFun logic level converter is a small device that safely steps down 5V signals to 3.3V and steps up 3.3V to 5V. This level converter also works with 2.8V and 1.8V devices.
The DS75176 is equivalent to the SN75176
Begone, hard-to-program USB devices! At the hands of my FT232RL chip, you will behave like a serial comm port!
he ST232 is a 2 driver, 2 receiver device following EIA/TIA-232 and V.28 communication standard.
The EFX-Tek RS-485 adapter is an ideal solution for putting multiple microcontrollers on a custom network.
The Parallax USB to RS-232 is a great little adapter that takes your mini-USB connector and converts it to a RS-232 interface!
The DTE RS-232 module is a tight and tidy way to convert RS-232 (computer-level) signals down to a microcontroller level signal strengths. DCE means it's configured as a "Data Communications Equipment" (with 9 holes).