I believe comments are important and it's a no-no to accept that programmers won't maintain them (maybe naive of me but progs should be taught to treat them seriously if they aren't already?).
On an old game I started using _standardized_ FIXME comments to ensure they can be grepped. I still use that technique nowadays.
It's important IMHO to standardize them by e.g. subsystem rather than let everyone add their own flavor of "//!!HACK!!.