For a long time, I have had two great Web hates: pages made up of PDFs and those using Flash animations. I realise now that to these I have to add a third, and for the same reason: they all undermine the openness and transparency that underlie the Web's enormous power.
I hate PDFs because they are opaque compared to Web pages. With the latter, you can see the underlying code and get at (in programming terms) individual elements of the page. This is important if you want to do clever Web 2.0-y things with content, such as mixing and matching (and mashing).
I hate Flash animations even more: they are not only opaque - there is no cyber-there there - they are barriers to my free navigation of the Web and waste my time as they download. In effect, they turn the Web into television.
To these, I must now add TinyURLs. In themselves, they are a great idea: too many Internet addresses have become long snaking strings of apparently random text. But the solution - to replace this with a unique but shorter URL beginning http://tinyurl.com commits the sin of obscuring the address, an essential component of the open Web.
So while I applaud TinyURL's rigorous terms of use, I never follow any TinyURLs in my Web wanderings, however easy and seductive they might be. For all I know, they might well be taking me straight to a PDF or Flash animation.