Lua is programming language described by its community as:
Lua is a powerful light-weight programming language designed for extending applications.
There are severals versions for many platforms :
S60 Lua for 2nd edition
Lua Epoc ToolKit (LETK) is a conversion of this powerful language to the Symbian S60 platform. There's no binary release but you can easily build it for your SDK version. LETK has been tested successfully with SDK S60 2.0.
S60 Lua for 3rd edition
Lua 5.1 for Symbian s60 3rd,but only run in the emulator at present(October 2006),it's a console .exe program without ui,and will be improved later.
Lua for Palm OS
Lua For PalmOS is a port of Lua5 to PalmOS.
Lua for PalmOS (Cobalt) is a port of Lua 5.1.1 to Cobalt version of PalmOS. Including some extensions to UI, Databases and VFS.
Lua for Psion
http://www.lua.org -- Lua - Artigo em português.