It was announced on the PS2Dev Forums that the newest version of Lua Player has been released by Shine.

v0.16 (all changes for this version by Shine)

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- Wlan:getIPAddress bugfix: now it returns nil on error and the IP address otherwise
- DNS resolving. Now you can write Socket.connect(“www.luaplayer.org”, 80) instead of Socket.connect(“212.227.39.202″, 80), thanks to ideas how to use the resolver lib from PSPRadio
- when loading JPEGs, the file was not closed
- System.md5sum bugfixing for the Windows version
- Wlan.useConnectionConfig index is 1 based instead of 0 based, like usual in Lua
- System.powerTick added: this prevents power off, now you can nail your PSP on a wall for your electronic painting :-)
- System.createDirectory, System.removeDirectory and System.removeFile added

The new functions are documented at http://wiki.ps2dev.org/psp:lua_player:functions.

You can download Lua Player v0.16 for Firmware 1.5 here.
You can download Lua Player v0.16 for Firmware 1.0 here

If you have a PSP with 2.00 firmware, try this EBOOT.PBP Loader, Lua Player included.

For those that do not know, Lua Player is a lua script player for the PSP. This allows for much easier creation of new games or porting of existing games. Take a look at the gallery for some examples of games made with Lua.