Considering that research money is just "eaten up" by the game, and doesn't give anything back until the tech is researched, I was wondering where exactly the money is going in a practical sense. Now, your largest cities are probably doing the most research, mainly because of the fact that they can put more money towards the research.

But where is the "master record" kept? When an AI steals a tech from you, I generally assume that they do it from the capital. So, here's a few tech ideas for Civ4:

1) Research is being done in the capital. If the capital gets lost, you lose the current tech you're researching.
2) A Forbidden Palace allows for two techs to be researched at once, except the second research can only be fueled by cash from the FP city and there's no max. number of turns.
3) Research can be "suspended" but the knowledge "decays" over time - say 10 beakers per turn, or something age-dependant. So let's say you're 5 turns from finishing theology, but Iron "pops up" in your territory somewhere and you decide you want to get to knights asap, but you don't want to lose the many turns of research you've put into theology. So, you "suspend" theology, build chivalry as fast as you can, then go back to researching theology with only a few turns of research lost. On a similar note, FP partial research carries over to the main research in the capital if the capital starts working on it(suppose the FP put 10 gpt into medicine for the 18 turns steam power was being researched...once SP is finished, medicine already has 180 gold put into it)