Idea: Transaction Logger

It would be great to create a device that logs all of my transactions (whatever the method used to purchase) that could be carried around while shopping. This would then enable consumers to do personal data-mining on all of their own transactions. This would be a unique tool to help consumers improve purchasing habits and make smarter decisions. Additional interesting product associations could also be calculated and analyzed.

Web Data Mining (for Business Intelligence)

Bamshad Mobasher teaches a nice Web Mining course entitled "Web Data Mining (for Business Intelligence)" at DePaul University in Illinois. Currently, it is one of the few courses dedicated solely to this topic. I expect, as time goes, the number of courses on this topic will grow dramatically.

Exploring Bayesian Methods

Bayesian methods can be used to deal with uncertainty.
Here are some links that help to explore the area:
Bayesian Inference
Empirical Bayes
Hierarchal Bayes
Bayesian Network
Bayes' theorem

Statistics Topics
Expected Value
Likelihood
Mean
Variance
Mean Squared Error (MSE)
Posterior Probability
Conditional, Joint, and Marginal Probability
Utility Functions (Link  2)

Distributions
Normal
Gamma
Poisson
Beta
Binomial
Conjugate Prior

Other Related Topics
Markov Chain Monte Carlo (MCMC)
Simulated Annealing
Tabu Search (Link 2)
Kalman Filter (Link 2)
Particle Filter
Directed Acyclic Graphs (DAG)
Markovian Random Field (MRF)
EM Algorithm (Bayesian Structural EM - Friedman)
Reading List of Bayesian Methods

Helpful Software
JavaBayes
Graphviz

Useful Java Libraries
Colt
Tomato

Web Content Mining: Bing Liu

Bing Liu from the University of Chicago is very interested in Web Content Mining. He compiled of list of references regarding the topic. In addition, he gave a tutorial on Web content mining in Chiba, Japan in May, 2005.