A. Side bets don't come without cost to the casinos. They are proprietary games and casinos must pay licensing fees to have the bets on their tables.

In order to earn their keep, side bets must generate enough action to pay the licensing fee as well as to make a profit for the house. Usually, the side bets generate plenty of action early in their life cycle, but the action erodes as players notice their money disappearing faster than on the base game.

Another potential cost relates to the time it takes to make payoffs. They can slow the game down so that the house makes less money on the main game. The side bets need to generate enough revenue to make up that difference as well as paying the licensing fee.

If and when electronic payoffs become more widely accepted, you can expect to see more side bets. Systems already exist to offer multiple side bets at the same table. Even at dealer-assisted, semi-automated tables where a human deals the cards but wagering is on an electronic betting pad, the side bets don't slow down the game. They're made instantly by the computerize system, and the game moves on.

A. Ultimate X Spin Poker is a new game from IGT that's just what it says: It puts the same multipliers on hands following winners that you get on Ultimate X.

The odds on Spin Poker games are the same as on games dealt in the traditional manner as long as the pay tables are the same. The nine paylines on Spin Poker are just nine video poker hands displayed as if they're on slot reels. If you took the cards from each payline and spread them out as nine traditional-looking hands, the results would be the same.

As for the Ultimate X wager, game manufacturer International Game Technology generally sets up its extra-bet bonuses so that the added wager will bring a payback percentage as high, or higher, than the base game.

Using 8-5 Jacks or Better as an example again, your overall payback percentage with Ultimate X is 97.9 percent on Triple Play versions and marginally higher at just under 98 percent on Five Play and Ten Play games.

Betting enough to get the Ultimate X multipliers raises the overall return so that it's higher than the 97.3 percent without Ultimate X.

However, you're doubling your wagers to get the multipliers. In 1,000 credits worth of wagers on the base game, your expected average loss would be 27 credits. If you double that to 2,000 credits in wagers to get the multiplier feature, your payback percentage increases but your average loss also increases to 42 credits.

Whether it's worth the extra bet to get the Ultimate X feature depends on your goals, preferences, and bankroll. Ultimate X increases the payback percentage and gives you a better shot at bigger wins, but there's a tradeoff in a bigger risk and higher average losses.