Wireless Network Security Help!?

I just set up my wireless network a couple of weeks ago and set up a WEP security thing on it that gives you a Hex key to log in and stuff, anyway I left my computer on all day and night yesterday while at work and I came home and clicked on my wireless monitor and under the connections it had:

IBM Visitor

retea

(My connection)

linksys

Visitor

I am on channel 11 and they are all on channel 6, Is this something to be concerned about? Sorry I am new at Wireless networking

Wireless Network Security Help!?viruses

well the best i recommend would be to change your password frequently and avoid switching on the wireless network the whole day.

Wireless Network Security Help!?antispam

What did you set the password as? It looks like you have some ppl mooching off your wireless connection..