On the first weekend in September I attended BarCampLondon, a tech community get together. To attend you need to give a presentation about, well anything, but best go for something that everyone else will be interested in.

I decided to (or should that be persuaded to) get things rolling by giving my presentation in the first slot, and opted to talk about the high tech treasure hunt game of Geocaching. Below are the links I promised to publish in the presentation.

In May 2000 the United States turned off the selective availability of the global positioning system that intern allowed the system to be fully used by the public. Someone had the great idea of hiding a stash and publishing it’s coordinates online for someone else to find, and find it they did. More about the history of Geocaching is available on the geocaching.com website owned by Groundspeak.

Although there are several cache listing sites where the location of these “Caches” are listed the most popular is geocaching.com, and in the UK we have a great resource at geocacheuk.com that collates statistics from geocaching.com and allows more advanced searches.

The UK does have a body that is formed by UK Geocachers to help UK Geocachers called the Geocaching Association of Great Britain.

Another site that I recommend having a look at is trigpointinguk.com that conatins a list of all the concrete trigpoints used by ordnance sevey. Because they rely on line of sight for navigation they are normally located in a place that comes with a stunning view and are often well worth a visit.

It is becoming more common for people to ask me what they need to download to protect there machine from viruses and spyware. The following is generic advice for most Windows users trying to protect there PC for free.

First let’s protect ourselves against viruses. I will now let you in to a secret, I would like to say that I am fully protected but I don’t run antivirus software on my development and media machines for technical reasons. Despite this I do recommend that you install a virus scanner on your machine under most circumstances.

I advice you not to use Norton Antivirus that is often preinstalled on new PCs and available through Google Pack. It is not a bad virus scanner, it has had many great reviews, it may well run well on higher spec machines, but it has significantly slowed down all the machines I have run it on.

Many say you get what you pay for when it comes to virus scanners, but while acknowledging the argument I believe a free scanner will be more than adequate for generic use. The best known free virus scanner is Grisoft’s AVG. This is free for personal use, works well and does not noticeably slow the machine.

A newcomer to the free antivirus offerings is Active Virus Shield. This is interesting as it has been created by Kaspersky Labs and is begin supplied by AOL, although you do not have to be an AOL user. I am currently evaluating Active Virus Shield and not going to compare these two virus scanners, but I will note that Active Virus Shield can be used legally on some networked machines that AVG can not.

Update: Active Virus Shield is no longer available for free from AOL but has been replaced with the equivalent McAfee Security Centre.

If you don’t have a virus scanner installed and want to quickly scan your computer I suggest checking out Trend Housecall. Although not a complete solution this will allow you to do a system scan from your browser.

Next you should consider using some antispyware software as having antivirus software running will not protect you against most spyware. I don’t claim to be up to date with all offerings, but I personally use both Spybot Search & Destroy 1.4 and SpywareBlaster 3.5 to both search for spyware and protect against it invading my machine.

Finally you should consider a software firewall. Windows XP SP2 has a firewall built in, but this is very basic and I have found spyware that has bypassed it. The free offerings available are the basic Zone Alarm and the more advanced Kerio (free version activated after 30 day trial of full version). I use Kerio but the more basic Zone Alarm may be a better option if you want to keep things simple.

Update: I have also been playing with the free Comodo Personal Firewall and it is fully featured and works well.

Please remember that all this software will not completely protect you from everything and not opening unexpected emails or running untrusted software is recommended.