Many applied problems give rise to generalised eigenvalue problems of the form Ay = s By, where A and B are operators of various possible types, and s is an eigenparameter. Two parameter embeddings Ay = s By - t Cy generate useful methods of attack, and can be traced back about a century, but new applications are still appearing. They provide ways to visualise simply some quite complicated phenomena, and in this talk I will discuss some older and newer ones that I have found interesting.