VM instruction implementation without huge switch()?

How would one go about making a virtual machine without using a huge and clumsy switch( opcode ) statement?

The architecture I'm implementing (DCPU-16) has about 35-40 different instructions.

>>61
Considering the C89 standard requires up to 257 (default + one for each byte, think of state machines), and C99 increased that to 1023 (no idea of the rationale for that one), 40 is certainly not large at all. C++ increased that even more to 16K(!)