in which I try immobilise tags for the bikes

I've been using that useful free Immobilise.com web site for some time to register valuable items.

It only really takes one splurge to set up, based on initially the most valuable/vulnerable items. Initially I simply listed a few things like iPhones and laptop computers and then have occasionally added a few more things like cameras and fancy lenses. It's good because you can list the items and then progressively fill in more info when there's time. An example was the various computers. I could list them and then add the serial numbers when I was next on the relevant device. I suppose it could be extended to anything with a serial number and does have the advantage of keeping all the information in one place.

The web-site lets you list the item, its serial number(s), identifying marks and even add notes and some photos. It's the citizen half of the National Mobile Property Register, which is the bit that the police use to identify stolen/lost property.

Police forces as well as main luggage handling services like railways and airlines all use this to follow up on serial numbers and markings to identify and re-unite property with owners.

I thought I'd extend it to my bicycles and sent away for their (paid for) Immobitag, which is a simple RFID device which is pushed into the bike frame, effectively providing a permanent electronic tag. Once its installed, it is almost impossible to remove, because its like a one way springy thing that embeds low into a tube on the bike.

A simple idea. It's not like the tracker on my car which sends out a signal if its been moved without authorisation, but it's still a useful additional aid to crime prevention.

I'm told the mainly free scheme works by the sale of the 'extras' like sheets of traceable tags and marker pens, so I don't mind spending a few bob to show some support.