To start, these presents that will truly appreciate in value. A silver spoon is nice indeed, but it will not be worth more later on. This is the same problem with a baby present or book - they are "one time gifts."
Investments, on the other hand, act as both a unique and very useful christening present for the child. What young person would not be able to use the money later on for schooling or rent? By giving financial instruments you also show that you have the child's best interest at heart. A recent study shows that more than 25% of Brits will actually be giving stocks or bonds this year to a loved one as a present! Why not as christening presents, too?
There are many ways to have investments, and the compound interest the savings account you set up will continue to make money by earning interest every year for the child. When it comes time to go to university or to buy a house, there will be more money for them then when you first gave it. It's really amazing that your gift can keep on giving like that!
To go about giving investments as christening presents, the exact specifics will depend on where you live. Talking to an investment company or a trusted accountant is a good idea. Don't be scared though - it can be done very easily, and is guaranteed to be the most useful christening present the child gets