How I like a drink, alcoholic of course, after the heavy lectures involving quantum mechanics.

That phrase contains the first fifteen decimal places of pi encoded in the length of the words. For more decimal places, simple increase the poem length:

Now, I wish I could recollect pi.

"Eureka," cried the great inventor.

Christmas Pudding; Christmas Pie

Is the problem's very center.

The above allows you to memorize the first twenty-one digits of pi. Not enough? Or not a good enough poem? Try this rework of Edgar Allen Poe's The Raven, with each word representing (sequentially) a digit of pi. The longest pi mnenomic is right around 4,000 words (with each one representing a digit of pi). That's a lot of pi.