DirectFB is a Direct Frame Buffer implementation of a set of graphics APIs implemented on top of the Linux Frame Buffer abstraction layer.
Goals of DirectFB:
+Small memory Footprint
+Maximize utilities of hardware 2D acceleration
+Support for simple multiple alpha blending modes
+No kernel modifications
+No library dependencies, except for libc
DirectFB runs on top of the Frame Buffer Device (/dev/fb0), and utilize hardware 2D acceleration (other features are experimental) with their (1) chipset drivers.
XDirectFB is a kind super-simple "X Server" for DirectFB
(1) MGA is supported, 40% documented, but all the 2D stuff is in perfect working order.