It's tough for parents today; the internet has so much to offer children, but also a lot of adult and inappropriate content.

However the European Union is providing 60m Euro in funding to provide parents and teachers with tools to keep their children safe while on the internet. It's likely that these tools will be based on open-source, so they will be usable world-wide.

It's already possible to use free tools to do this today, but it's not yet easy enough. The key terms that you encounter with web or mail filtering are whitelist and blacklist; a whitelist or YES-list is a list of good sites/addresses that are allowed through, a blacklist or NO-list is a list of known bad sites. If you want the safest solution, you can use a whitelist and prevent anything that is not on that list from coming through. A blacklist is typically only useful if you subscribe to an update service (similar to virus protection); even with regular updates they can never be entirely safe, so I don't recommend them. It is also possible to use filters that look for keywords in the address name or in the content; if your list of keywords is long enough, this is far safer.

Here are some specific tools you might like to take a closer look at:

• A web proxy such as the popular Squid can stop inappropriate content as well as caching content for faster access; DansGuardian is far easier to use and supports keyword-based filters
• For blocking spam and adult mail, Postfix is an advanced mail-processing program similar to the popular sendmail; it supports a variety of techniques for stopping inappropriate mail or spam; for example, see this Newsforge article which uses a Postfix after content filter

Most free tools work best on UNIX-based systems such as Linux and Solaris. If your children use Windows, you can setup a separate machine to act as an internet gateway.

But if you're not interested in technology, there are several good sites where you can get more advice; the Filtering Software site contains reviews of several easy-to-use packages, and Phil Bradleys's Child Safe Internet has a host of links and useful information.

It's great to see Sun Ray now available for broadband. Folks who know SunRay thin clients tend to like their instant boot, solid state electronics (no moving parts, no disks), silence (a room full of Sun Rays is eerily quiet, nice if you're in a shared office, a call centre or a library), cool-ness (use minimal power, generate negligible heat) and their statelessness (if anyone steals a Sun Ray, they take no data; the flip side is that you can walk from one Sun Ray to another and instantly get back your desktop session by just inserting a card - check out our Mary packing her "laptop" - that's right, that little card is all she needs to access her desktop).

But now you can get all that, and take your Sun Ray home or on the road. Secure, low-cost, centrally managed computing and storage - simplicity itself. You might not believe it until you've seen it, and once you've seen it, you may not want to go back to managing your own desktop.

As someone who just last week had the distinct non-pleasure of trying to retrieve all the data I could from my laptop hard drive (ok tell me, who actually manages to do backup often enough that they don't lose some data? ;), not to mention fighting spyware from the time I used Internet Explorer on Windows, I'm seriously considering switching to SunRay full time; life really is too short to fight the problems of a thick client laptop.

Update: mere minutes after posting this earlier, a fellow Sun blogger Paul Rogers has another tale of woe about a laptop. And they can affect fertility too? ;)