Plenty of them out there, but not many ones for free. I don't know if you're looking for free only.
That said, if you're worried about people spying on you (whether it be other users if the wifi only uses WEP or WPA but not WPA2, the company since they can see all traffic heading out to the internet, or their ISP
), you are simply shifting who is able to see the traffic. With a VPN, the company and peers on the network can no longer see the traffic, but the VPN hosting company can. With some of the shady ones out there, I'd be a little more worried about that than your company. Case in point, a popular proxy said they did not log any traffic, and were completely anonymous. Well, over the last few months, it turned out that they were logging everything and turned over all the records to the US government. I'm sure there were more than one or two dumb criminals that used that proxy service to cover their tracks... which weren't covered.
How does that happen? Well, some of these VPN providers are based in some remote country where the privacy laws are non-existent. Sure, they may claim on their site that they don't log traffic, track you, or report your actions to others, but how do you know? What would happen if they actually do? Nothing; they operate in a country that doesn't care.
On the other hand, your employer has to follow worker's rights laws, privacy laws, and depending on how big they are and whether they operate in other countries, they may not log any traffic due to other privacy laws in other countries that make it simpler to just not log traffic at all. If you work for a medium sized business (say, 6,000+ employees) or larger, in most cases the traffic is logged for a few days only, then deleted, and unless you are undergoing an investigation, there won't be any more logs kept.
So, while the VPN recommendation is a good one (I use my own home-brewed VPN connection hosted on my own server, where I know nobody else is 'watching' the traffic), don't assume it doesn't come without risks, either.
I know I didn't give a specific recommendation for a VPN provider, which is what you wanted, but many people think a VPN is secure and perfect, but it is not. As long as you realize the risks, you'll be fine.
The above post is my opinion. Don't like it? Don't read it.