It seems Omni must have read my post about free trials*, because they're handing out an Internet coupon for a free day pass. Simply print it out (in colour!), cut it out and hand it to a bus driver any day during SoCal Rideshare Week, which happens to be this week, 3-7 October.
You'll have to answer a one-question survey to get the link to the coupon.
*They actually do this a lot, so I can't really take credit.