A large number of thesauri and controlled terminologies are in use across a variety of subject groups. Some of these are available on-line, whilst others are either restricted to weighty paper versions or tightly integrated with proprietary software products.
The following documents and reports include useful background information.
The links, below, point to some of the better examples of on-line applications, which you might like to look at before the workshop.
And this set of links points to whole groups of thesauri...
The links, below, point to a small number of applications which make some use of terminological control to aid browsing.