Hello,
in this thread http://blenderartists.org/forum/showthread.php?t=107208 CyaNn has referred to very smart simulation of HDRI (or to be precise LDRI) lighting in Blender Internal (actually it is fully possible only in Yafray).
I thought it maybe very useful for all Blender users.
Here is the original tutorial in french.
And here is dirt translation by Google transaltor (pictures are quite self-explanatory).
Original author of the tutorial is GFab3D from Blender Clan.
I am also adding example blend file with packed lighting textures - HDRIblend