You can use one Mac to share an internet connection with another Mac that doesn't have one.
Check the box for Internet Sharing in the Sharing prefs.
Hook them together.
Quick Tip: Share Another Mac's Internet ConnectionCategories: Mastering the Mac
Last week I had to buy a new Mac Pro to replace a PowerMac that blew up. Normally this is good news, but in this case I wasn't expecting to be spending that kind of money right now. I also didn't expect that Mac Pros Airport cards are not user installable like all other Macs.
Since I didn't have time to wait for the Geniuses at the Apple Store to install it, I had to take it back to the studio without wireless connectivity and keep working. I figured I could bring it back at the weekend where I could afford to be without the Mac for a while.
So what can you do when your Airport card is down or not even there?
I remembered seeing a bit about Internet Sharing, so I looked it up and there was my solution: Use my PowerBook's connection to get my Mac Pro on the internet. And all I needed was an ethernet cable.
All I had to do was go to the Sharing Preferences on my PowerBook and check the Internet Sharing box, and select which connection to the internet and which connection to my Mac Pro. In my case, I selected Share my Airport connection via Ethernet, then hooked up my two Macs with an ethernet cable. See below.
That was it! This kind of ease of use is why we all use Macs. Now this makes me wonder if one can share someone's wireless connection on a protected network this way, like in Starbucks or a hotel service. If anyone has tried, let us know in the Comments below.
Note: In general, it's wise to only turn on the Sharing options that you need. So if you aren't using Internet Sharing, you should probably keep it turned off.