I tend to use them all the time, when calling from an application bitmasks provide a easy way to filter data without having to add new parameters.

E.g.

create procedure spc_my_proc

@include_filter int = 0

, @exclude_filter int = 0

as begin

select a.a, a.b, a.c

from table a

where a.flags & @include_flags = @include_flags

and a.flags & @exclude_flags = 0

end

That makes retrieving data easy but you have to be aware that it won't work well with large datasets as it doesn't use an index. I find that pretty easy to read too.