fairs as source - (Oct/11/2006 )
On trade fairs as for example Biotechnica ( http://www.biotechnica.de/homepage_d?x=1 ) most of the exhibiting companies offer free advertisment stuff (pens, DNA ladders, posters, calculators, dyes, and so on). We use since 1 year free DNA size markers we got from fairs or as gift in orders.
Sometimes you have to be a little bit demanding and ask for free stuff ("We are interested in your new Taq/RE/..., please can you send us a sample?", which also works on annoying sales representative visits), and some students are real collectors or better hunters for samples.
But I don't know how common such fairs are in other countries.
me and my friend r crazy abt pens so we used to collect pens from all vendors in conferences. also we would get other stuff as well.
its fun !!!