SSD1306Ascii is an unbuffered character only library for small OLED displays like the Adafruit 1.3" and 0.96" Monochrome displays.
Many low cost OLED displays with SSD1306 controllers are available on ebay.
SSD1306Ascii runs on Arduino AVR boards, Arduino Due and many other Arduino style boards that have the SPI or Wire library.
The SSD1306Ascii library only requires a few bytes of RAM.
Here is memory use for the SPI "Hello world!" example with scrolling disabled:
Sketch uses 2,938 bytes (9%) of program storage space. Maximum is 32,256 bytes.
Global variables use 58 bytes (2%) of dynamic memory, leaving 1,995 bytes for local variables. Maximum is 2,048 bytes.