As one of the top 10 development boards under $10, the TXB0304EVM has a lot to offer.
A 4-bit autodirection sensitive voltage level translator for push pull operations between .9V and 3.6V that lets you prototype without the full board.
Price: $4.97
With applications such as industrial, enterprise, telecom, and personal electronics; this evaluation board provides the capability for interfacing devices or systems operating at different interface voltages with one another. The A and B ports allow for low-voltage bidirectional operation anywhere between the voltage nodes. Without the need for a full board development, this evaluation board provides peripheral header style pads for connection to each device pin on the board.