How about "inline" for manifest constants?

[Russell Lewis]

inline int x = 3;

Where the "inline" keyword means "the compiler is free to not allocate 
any storage for this constant."  In particular, this means that it would 
be a syntax error to either:
	1) Take the address of an inline constant
	2) Change its value

Whether or not the compiler actually inlines all instances or not is 
implementation-specific.