Humm I wonder if you really what what you are asking for...
I am looking to make my Mac invisible on the network that I am connected to. Preferably software that can hide the sites I am viewing
Hide from whom how? Are you just embarrassed when your SO finds the browser history full of "research sites"? Are you worried about a third party watching you traffic? Are you trying to get arround teh company's web proxy?
The reason I ask is that each of those would need to be addressed in a different way.
If you "hide" your IP you cannot send or recieve anything, althought your could monitor other traffic. Now you may want an anonomizer like you mention here...
I found software called Anonymizer, which seems very effective, but they charge on a monthly basis.
This is basically just a proxy where you are sending your request to there computer and then they forward it on so that it looks like it is from them. That only really provides anonyity on the far end of the connection, if I am sniffing traffic on your subnet I'll still know what you are up to. (I assume that they are using ssl so that is not really that easy.) Also if you do go this route remember that you need to trust the middle guy to protect you.
There is an interesting idea called Crowds which is kind of a randomized P2P proxy. In that case when you make a connection it comes out of someone elses computer. If you get enough people together this provides a degree of anonymity but it may not be the best thing to run in a work environment. Other people's connections will be made from your computer... Honest boss it wasn't me looking a nekkidpuppies.com some one was using the anonimizer on my computer for that
As for no popups that was in another thread here just two days ago...
Have fun,
-Eric
P.S. Just a bit of commentairy here. I can help you do almost anything in this space that you would like, but I won't. I will help you protect your privacy and the security of your info, but I won't go into how to violate some else's. But I am sure that your intent is pure
P.P.S. Has anyone seen my tinfoil hat?