What kind of things do you have in mind?
As above, you can learn a deck stack. Mnemonica will be reprinted, or learn another while you wait. Si Stebbins is a thought of you want something that uses calculation while you wait to memorize Mnemonica.
Get a memory book and learn great feats of memory. Learn to memorize a shuffled deck on the fly (look for Memory Palace), the world record is around 25 seconds last time I checked. If you like the idea of tracking faros, expert card technique has charts etc., but that's just the tip of the iceberg. In addition to Marlo mentioned above see The Collected works of Alex Elmsley Vol. 2. If you are into math look into anything by Persi Diaconis including his mathematical journal papers on shuffling (wicked grin) and check out his "Magical Mathematics" for inspiration.
If you really want to use memorization and calculation then do what I did, learn Mnemonica and culling. I can secretly put a shuffled deck into Mnemonica order with 6 culls. You will however need to work this into a full routine with tricks in between, or incorporating, the culls to prevent the spectators from wandering (or dozing) off. By itself it takes a few minutes. Take this route only if it sounds like fun, your time would certainly be more efficiently spent learning other things. But if you want memorization and calculation there's plenty to be had here.
It sounds like you might like a memory book. Other than deck stacks much of the magic literature will just teach you how to fake feats of memory. You may enjoy learning the real thing. There are many books, I have not found one that seems best. Harry Lorayne has several, but there are others.
Let us know what you'd like to learn and we'll try point you in the right direction.