Must I own a copy of MS SQL Server to employ a 2- user split database over a network for personal use?

I want my girlfriend and I to be able to access my database (kinky). I want the table/tables on a logical drive on my partition on my laptop (kinkier still). Access 2007 is not a database server I am made to understand.

Do I need some version of MS SQL Server on my laptop? We both have Access 2007. I have a Verizon Wireless air card connection which I suspect will be a problem, and she uses a home wifi network through the phone company, which might also be a problem.

I want her to be able to update a record and it all reside on my laptop where the tables reside. This presumes that we are both connected to the net. I'm suspecting that this is the kind of scenario that Sharepoint was designed for.

I'm a newbie here so go easy on the techno-talk if you can. Thanks

What kind of software/hardware is necessary to do this. I should say the biggest reason for doing this is bragging rights, okay. The database in question will be very simple.

Some men brag about this, some men brag about that. I brag about stuff I figure out. However, I'll be sure to list you-all in the credits.