I work with a wide variety of businesses from heavy manufacturing to business consultancy and IT. See Food Design Projects here
Working with IT companies is something I really enjoy as we usually get along really well. This is probably because I'm a little bit of a 'techie' and so I understand the industry (however I can't talk code so don't go there!).
The challenge in this industry is to communicate complex capabilities in a simple, clear and visually pleasing way. This could involve marketing a piece of software in an infographic format which can be used across a mulitiude of media such as a sales brochures, online, an email marketing campaign...you get the idea!