Another Proxy Server Query

[frogpatrol]

Lately, I have been utilizing proxy servers more and more for various sites.

 

However, in the cases where I have a membership to a particular site, I am first prompted for my password (which makes sense), and then I get a message which says that the proxy server company must be trusted with my password and log-in details.

 

So, the query is as follows: Just how safe are proxies? Has anyone had their pword or details used for illegal purposes? Or does it just depend on the proxy server itself? Maybe some can be trusted and othes can't?

 

Thanks.

 

froggo