The interweb has seen the rise of absolutely horrible code that's freely available. This applies across the languages and even perl (shock-horror). Poor Javascript has always been on the net and is always coming back to haunt us. This has been made even worse by the fact that different browsers have different implementations of javascript.
So why am I even talking about this? Well... at my current company, we've got some very very funky tangram based frameworking and a lot of it is concerned with Javascript. Basically we've designed a toolkit that's mainly cross-browser and our tangram framework has been made into a RAD tool... all our data infrastructure automatically generates javascript widgets on the front side. I was hoping to have done a talk about this at YAPC::EU::2004, lest it's not going to happen.
So, this is all proprietary... so not much use to you fellas, so why am I talking about it? Well... my housemate who works with me, is now doing a toolkit that's been written from scratch at a 3rd generation. Oh yes... it's LGPL =0)