Update: I haven't really been using this, since the bandwidth required is a bit... excessive. I think I'll stick to duplicity + external hard drive.

Duplicity is a backup program that only backs up the files (and parts of files) that have been modified since the last backup. Built on FLOSS (rsync, GnuPG, tar, and rdiff), it allows efficient, locally encrypted, remote backups.

Amazon S3 is a web service that provides cheap, distributed, redundant, web-accessible storage. S3 currently charges only $0.15 per GB-month storage and $0.10 per GB upload. The API is based on HTTP requests such as GET, POST, PUT, and DELETE.

The following is a description of how I made use of these to back up my laptop, which runs Ubuntu Feisty Fawn.

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Two armies are preparing to attack a city from opposite sides. The General of army A is orchestrating the attack, and has decided that they must attack simultaneously at noon on March 3rd to succeed. He sends a sealed, encrypted letter by messenger across the valley to the General of army B, informing him of the plan, but worries that the messenger might be intercepted, so General B may not be informed. (If the attack is not simultaneous, both attacking armies will be destroyed by the defenders.)

As it so happens, General B does receive the message, but knows that General A cannot be sure of this. He sends back a receipt of the attack plan. Then he wonders... will it go through? What if General A does not receive it and decides not to attack, being unsure of B's knowledge? And even if General A sends over an acknowledgment of the plan's receipt, there is no guarantee it will arrive.

Given this faulty communication channel, how will the generals coordinate their plan?

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I'm having difficulty deciding what is the best approach to returning from a POST request to one's web app. I'd like to deliver messages to the user about the results of the request, I want to avoid some nasty POST-related browser behavior, and proper bookmarking would be sweet, too. Unfortunately, it seems I can only have 2 out of the 3 with any given strategy.

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The existing comment-tracking systems that I know of just aren't enough. CoComment is buggy and fails to properly parse out comments for a number of blogs, and is missing a number of important features. (Float unread to top of list, for example, or track a URL without visiting it.) Co.mments.com has a much nicer interface and tracks better, but lacks a Firefox extension and some of the advanced features of CoComment.

Rather than simply whining about the lack of excellent trackers, I want to help the existing ones improve. Here I present most of algorithm to parse out comments from an unfamiliar blog template.

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My local paper, the Daily Progress, ran a story today about a proposal to install 30 security cameras on the Downtown Mall. I think there's a wrong way to do this, and a right way. I'll explain why the wrong way is wrong, and suggest a scheme that could lead to a right (or better) way.

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