In our case we'd like to use ajax.poll method (ajax.js) for one of our add-ons but we need to have possibility to start request immediately and continue polling using 'interval' option.

In current implementation method ajax.poll uses 'interval' option for initial timeout.

function poll(options) {
        options = $.extend({
            pollTimeout: 60000,
            interval: 500,
            tick: $.noop
        }, options);

// ...
// something like options.delay it would be nice to have
setTimeout(doPoll, options.interval);
// ...
}