There are several kinds of clay; Fimo and Creall-therm are the most used ones for ordinary kitchen ovens. Both can be obtained in many colours and intermixed.

Fimo:
* Clay canes (millefiori; i.e. round flower canes)
* Classic (24 colours)
* Soft (48 colours)
* Mixquick
* Fimo for dolls
* Liquid Fimo Decorating Gel (New)

Mixquick
It looks like white coloured clay but it is a very good kneeding medium for restoring stiff clay (Classic too) back to a reusable condition and it will not alter the color of your polymer clay.

Liquid Fimo
Just read about it, very new, a liquid polymer gel. It's an excellent adhesion medium for connecting unbaked or baked polymer clay. You can also paint with it or use it to transfer images from photographs, newspapers and magazines.
Has anybody used this stuff already? Please inform me.

Creall-therm:
* Creall-therm junior (6 colours)
* Creall-therm Professional (several colours)
* Creall-form (6 colours)

Junior is easy to use for children. It stays soft and easy to handle.

Professional is a special kind of clay for professionals and people like me.

Creall-form is the clay for the small ones. It does not dry quickly and is very easy to handle.

Mixing
If you mix two or three colours you get beautiful shaded colours (marbly), mix it further and a new colour emerges. Take care, do not use too much black. It affects the result tremendously.

Baking and varnishing
The clay has to be in the oven for about 30 minutes, temperature 265 degrees F / 130 degrees C. Ventilate the room the oven is in! It is very important to let the workpiece cool off. It is not necessary but you can varnish your creation. The upside is that it will gather less dust, the downside is that if it is broken or damaged you have to repare it with glue. If it is not varnished you can always repare it with clay and bake it again. Same time, same temperature.