[TeMPOraL]

To take your example - assume I target you personally, and beyond the list of Google searches, I managed to get hold of the list of times (with minute-or-better precision) you made requests to Google Search (say, I hacked/subpoenaed your ISP). Taken together and if large enough, the two datasets would allow me to build a statistical profile of your possible interests - even though in the original dataset you're bucketed together with lots of people, each time you do the search (second dataset) you're bucketed with different people.

Gaining access to other data - like e.g. your country of residence + aggregated popularity of search terms for each country - would let me refine your statistical profile further.

[joshuamorton]

That would potentially work, but I expect that it would require a dataset of size larger than the average lifespan of a person (2.4 million google searches per minute).