Do you secure your wireless network?

I just recently (after too long of a wait) was able to set up a cable modem in my new apartment. I bought a new wireless router and opted to keep my network open. I’m on the top floor (they call it the fourth but to anyone who knows how to count it’s the 5th) and it’s a fairly weak signal since I only need it to cover my apartment. There are two secured wifi networks within range of me (one on one side of the house, the other on the other), so I’m not too worried about anyone getting in.

In this situation, would you secure the network? Do you have use WEP on your own network?