I’m not sure how I missed the original announcement of Simple List Extensions (SLE) for feeds, but better late than never.

SLE is a very simple specification to extend feeds syntax to better support some common scenarios that weren’t covered with original specifications of RSS and Atom. Previously there was no way to tell feed readers/aggregators to display feed items in fixed order (e.g. feed with most popular stories of the day) or delete items not present in feed anymore (e.g. auction site feed with items matching a query).

SLE also adds support for grouping and filtering of feed items, which might not be very useful with you average 10-item feed, but will be, if feeds will indeed become a general mechanism for transporting data and not only a tool to highlight most recent bunch of updates. In any case, you can read a very short specification or visit latest announcement which includes more explanatory links to why and how they can and already are used.

By the way, I’m not sure if any reader apart from beta of IE7 already supports SLE, but I expect that most of them will soon. There’s little reason not to.

One of more popular javascript scripts I’ve written is a simple function that hides an email address from spiders by constructing a mailto link on page load. So far it has worked quite well.

Lately I started to have my doubts about this approach though. There was a series of articles a while ago about Google’s new Mozilla-based spider that I didn’t take too seriously at the time. However, even if not true then, it’s still only a matter of time before a spider like this will show up. The new found popularity of AJAX/Javascript simply guarantees that, since search engines can’t and won’t give up indexing content hidden behind fancy scripts.

Which means that my script will stop working in not so distant future as will all email obfuscating scripts out there. If it can be seen by a human, then it will be seen by a spider. So is there a way to publish my email address without it becoming public through search engines indexes, which is where most spammers seem to get our emails?

I could write a robots.txt file, which would exempt my contact page from being indexed at all. But this is a rather crude approach, since it means nothing on that page will get indexed. I could move email information to a separate page to let other contact data get indexed, but this is hardly any nicer.

What I’d really want is to be able to tell to search engines that only a part of my document is off limits. I don’t think there’s currently a way to do this, but if anyone has an idea how to do it, I’d really like to hear it.

Update: I think all efforts, including mine, to prevent spammers from collecting published addresses are ultimately doomed. The basic premise of all such approaches is to cloak an address in a way that spider can’t see it or can’t recognize it if it does. By basing spider on something like Mozilla, there won’t be any difference between what spider sees and what user does. There’s a similar problem with recognition. As spiders gets smarter, as they invariably do, you’ll be getting ever growing overlap between smartest spiders and stupidest users until it’s big enough to be unacceptable.

So we’ll either put up contact forms or I hope move to defending our inboxes with smart spam filters (those who haven’t yet).

I recently noticed a changing behavior in how my family and friends go about buying a new mobile phone. The reason they have a mobile is to receive and make phone calls, but their selection of a model to buy is based mostly on secondary functions like built-in camera.

In itself this isn’t surprising. It’s normal and common that when features become ubiquitous, competition and differentiation moves elsewhere. Basic functionality of phones has certainly been fulfilled and it’s difficult to add a new call-related feature that would be a significant progress.

But what I find utterly fascinating is something else. Even though primary functions play no part in selection of a phone, they are still the main if not the only reason why we have them. In fact, they are what we use most and we wouldn’t buy phones otherwise.

So here’s an interesting dichotomy. Which phone is bought and when has nothing to do with why we have it or little to do with how we use it. We think we’re buying a phone and we’ll use it as a phone most of the time, but it’s features like camera or wifi that actually make a sale.

I’ve been thinking about it for a couple of days and I can’t think of any other product or service, where buyers would display the same behavior, but I have no doubt that this is only due my lack of imagination.