I do not link to sites which use Javascript or Frames without providing <NOSCRIPT> or <NOFRAMES> alternatives, or a generic version of pages, for those without Javascript or Frames enabled.
Such a site is inaccessible to someone not having Javascript or Frames enabled and is therefore excluding people from using the site on the basis of what setup they use.
The primary menace these days is the use of Javascript applets for navigation links to other pages within the site without providing a text alternative for the link. So, if someone has scripting switched off, or doesn't have it on their browser, the links will be invisible to them, they won't even know there are links there at all and so the site is completely unusable to them.
What makes it all the more irritating is that bloated applets are being used to do what can be done with one line per link in HTML. So not only does it not display, it's totally unnecessary and makes the page much bigger than it needs to be so it takes much longer to download than it should.
Similarly with making graphics links without adding text alternatives. As more and more sites become bloated with huge graphics, many users now do their initial browsing with graphics switched off for speed - when they find what they're looking for they switch on the graphics. If they arrive at your page and can't see anything other than a load of little boxes saying "image" without further info, don't imagine they will switch graphics on just to see what's there - 9 times out of 10 they won't, they'll simply hit the 'back' button on their browser and go elsewhere. Don't presume that people use the web in the way you would like them to use it - read the research as to how they actually DO use it and build your site accordingly.
Using Javascript applets or graphics for links without providing plain text alternatives is probably the stupidest and most selfish of all the elementary mistakes currently blighting the web. For example, how on earth is a blind person going to know where the links are without text alternatives? Do you really want your website only to be visited by those with perfect vision and Javascript? This site uses graphic buttons for links - but every one of them has a text alternative. If you switch off graphics on your browser you'll see that the site is still quite easily navigable using the text alternatives. It takes a few seconds in writing the page to do this - not to do it is inexcusable and simply drives people away in irritation. If you don't know how to do it, or can't be bothered, then you shouldn't be building websites.
Thankfully, this practise will shortly be against the law in several countries, including the USA. Legislation is currently being discussed regarding enforcing online the laws governing disabled accessibility. So, if you are using scripting languages with no alternative provision you may be deemed to be in breach of laws which ensure access for people with disabilities. You'll find it much cheaper to fix it now before the law forces you to.
The argument against the indisciminate use of frames has been well put by Jakob Nielson in his excellent article Frames Suck (Most of the Time) What I will say is that if the <NOFRAMES> tag on a site says nothing but "This page uses frames, but your browser doesn't support them", I won't link to it. Telling someone they have to get a new browser in order to read the information on your site is insulting and is a very fast way to lose friends - and potential audience/customers.
I do not link to sites which carry banner ads for products or services unrelated to the content of the site.
Or, more precisely, if a site has banner ads for online gambling or porn sites or suchlike, I will not link to it.
I am not opposed to advertising where appropriate, however, so if it carries ads for, say, Amazon.com or other online CD or book outlets or something else related to the site's content, I will quite happily link to it.
