Unwanted Computer in "shared" folder

I visited an internet cafe today with my apple macbook pro on leopard. While I was browsing yahoo etc. a "shared computer" came up under my shared folder.
It said: mynamecomputer "connected as guest"
Does this mean somebody on the same ISP has made their computer visible or a file visible they want to share?
Could they access anything on my computer? I have no passwords set for my wireless just a master password for logging onto my computer.
Would the computer ask for a password if somebody tries to get to my information or desktop?

One of the dangers of visiting an Internet Cafe or someplace like Starbucks which offer open internet service is that there is no security. Just make sure you do not have sharing turned on: System Preferences, Sharing. Remove check from any box that might be annotated. Also, System Preferences, Accounts. Turn off the Guest Account if it's activated.

AND: System Preferences, Security. Check the box that says "Disable automatic login". Also make sure your firewall is on and is using "stealth mode".

The computer that appeared under your shared folder is someone who for some reason has sharing turned on.

While at places like an Internet Cafe or Starbucks, never access your bank account or make any other transaction that might compromise your security, credit card info, etc.

Regards.

chscag said:

AND: System Preferences, Security. Check the box that says "Disable automatic login". Also make sure your firewall is on and is using "stealth mode".

Click to expand...

"Stealth Mode"...I love the terminology!
Kind of like a "lurker" on an internet forum..."I'm in stealth mode!"

- Nick

Also go into System Preferences > Networking > Advanced >Airport and make sure no other network is listed there. If so highlight it and hit the little minus (-) button.

Thank you so much. So if I have this correct there should be no threat as such to the information on my computer? I can not remember if the "shared settings were on or off but if they were on it will still ask another user for a password to get into my account correct? (I have a master password on my computer)
Is there any way to check if any information was accessed?
This user most probably just had his computer visible.....?