One thing every model railroader has to use at some point is glue. And sometimes you have to glue different things together.
For example, what's the best glue to use you want to attach plastic to styrofoam? (Lepages Epoxy). How about metal to plastic? (LePage's Metal Epoxy or J-B Weld; clamping can make the difference between success and failure.) What about plastic to wood? (Goop.)
All this information, and much more, can be found at http://www.thistothat.com/ (Motto: "Because people have a need to glue things to other things.") At the This to That website you can find out what glues to use for various materials. The site also provides helpful hints (e.g. it's a good idea to clean metal with steel wool or sandpaper before gluing, because rust never sleeps). It also provides non-toxic alternatives whenever a toxic glue is suggested as being best. The materials covered include wood, plastic, styrofoam, glass, ceramics and others.