This card has no cost to use, but also has no guarantee of working against the opponent. Use it against non-critical cards or when your opponent's hand is low in cards. If you want a more sure-fire way of negating a Spell Card, some alternatives are "Dark Bribe", "Magic Jammer", "Pollinosis" or "Solemn Judgment".
Chain this to the activation of Pendulum Scales. The opponent cannot discard a Pendulum Monster to stop it, since it is not considered a Spell Card in the hand, and if the Pendulum Scale is negated it goes to the Graveyard instead of the Extra Deck.
Use this card while "Splendid Venus" is on your side of the field for a sure-fire way to negate your opponents Spell Card.
You can also play this in a Discard Deck to increase the chances of it working in either case.
The advantage this card has over other negation cards like "Dark Bribe" or "Magic Jammer" is that no matter the outcome, this card is a +0, unlike the others which are a -1.
Use it in "X-Saber" deck and make your opponent discard another card.
You can use this card against "Infernity" decks, as they will likely have no cards in their hand to negate this card's effect.
This card will create a difficult situation for your opponent in a deck centered around "Van'Dalgyon the Dark Dragon Lord" if they target it with "Mystical Space Typhoon". Normally negating this card's effect would have no purpose in this situation but if you have "Van'Dalgyon" in your hand and they let "Magic Drain" negate "Mystical Space Typhoon" then you can summon it and inflict 1500 damage to them. Alternatively they might discard a Spell Card even when you don't have "Van'Dalgyon" in your hand.
This card is great to side for tournament play in that all tournament decks have either very few spell cards or cards that they wont want to get rid of. In certain scenarios, this puts your opponent between a rock and a hard place, and can force them to send to the graveyard a much needed spell card.