Convert it to wifi access point.

Sorry, I am newbie with Mac. I want to start wifi network with mac mini as wifi access point (i.e.wifi hotspot without any wireless network security).I have dsl modem to mac mini (ethernet connection) and want my macbook and mobile to access internet via mac mini. I want to create hotspot without any wireless network security on mac mini to specially test messenger (like skype,yahoo etc) on my mobile in hotspot environment.

Please can some one tell me how to set up wireless networking (wifi hotspot) on mac mini + internet sharing. (I understand macbook & mobile will have no problem connecting to mac mini once hotspot is setup on mac mini)

Thanking you in advance for your attention and answers...

For Tiger go to Sytem Preferences->Sharing->Internet Tab and choose
"share my connection from [built-in ethernet]" to "computers using [airport]"

For Leopard go to System Preferences->Sharing->Checkmark Internet Sharing and choose "share my connection from [built-in ethernet]" to "computers using [airport]"