Unboxing a value to a different type

Conversions between built-in value types is commonplace. Some built-in conversions are implicit and some have to be explicitly done through cast operations. Here are some examples:

byte b = 255;
int i = b; // implicit conversion
double d = i; // another implicit conversion
decimal dm = (decimal)d; // explicit conversion

What if we try to do type conversion while unboxing? Putting another way - what is the outcome if we unbox a value to a different value type?

object ob = b; // box byte 'b' from above
// unbox b to an int
int ubi = (int)ob;  

What would be the value of ubi?