Thanks a lot for the schematic. It will definitely do the job. What I like in particular, is that the circuit does not draw any current when in off position. I will try to build it.
As far as substituting the relay with a triac, I am not sure how would that work, as the relay contacts are in parallel to the push button - this configuration allows the 555 to be supplied after the push button is released. If you have a particular configuration in mind, I'd like to see it.
Again, thanks a lot!!