I've been reading a few articles about how social networks and mobile operators feel like they own their customers.

I think personalisation is a great thing. If Facebook or my phone company can give me a personalised service - or discounts that I'm going to use - then I'm all for it. However, how much of your personal privacy would you be prepared to sacrifice in order to receive what level of benefits?

I think Phorm are evil for not informing their customers of their illegal trials - I also think Facebook's Beacon needed much stronger privacy rules. But I don't think there's anything fundamentally wrong with an informed, opt in, system to hold a mirror up to your preferences.

Let's take an example. Google Mail scans your emails and presents you with targeted advertising based on the contents. I think that's quite useful - if I'm emailing someone about a holiday in Italy, I'd rather see adverts for Venice than for baby powder. I understand what Google are doing and I've agreed to it.

Let's apply that thinking to mobile. Imagine that I've knowingly opted-in to allow adverts based on my behaviour. Consider the following scenarios.

I'm always dialling Domino's Pizza from my mobile. My mobile operator sees that behaviour and, the next time I'm on their site, they offer me a discount at Papa John's pizza.

I quite like that idea. See what I'm doing and target me with something that will probably be useful.

Let's go a step further.

I send a text to several friends which reads

Fancy going for a pint tonight? First round is on me :-)

My mobile operator then sends me a text back saying

Get £1 off Magners New Peach Cider tonight - show this text at your local Weatherspoons for your discount. Click here to find your local.

Even better! I'm getting relevant stuff just for doing what I usually do. Offers for me - ad revenue for my mobile operator - eyeballs for the advertisers.

If this was all opt-in - and I could stop at any time - is there anything wrong with this? Is there a "Dark Side" to behavioural advertising?

Consider the following scenarios.

I'm always dialling Alcoholics Anonymous from my mobile. My mobile operator sees that behaviour and, the next time I'm on their site, they offer me a discount on Smirnoff Vodka.

Let's go a step further.

I send a text to several friends which reads

Fancy going for a pint tonight? I've left my wife and am taking the kids with me :-(

My mobile operator then sends me a text back saying

Looking for a cheap divorce lawyer? Click here to find your local. Or dial +44800......

Hmmmm.... Not so nice now. Is it?

Personalisation, Privacy and Social Norms can sometime clash in the most creative of ways.