We use Lithium in our digicam, the cost isn't that bas if you buy them from somepleace like Sams club and the weight savings and long life even compared to NiMH makes it worth it.
I store some of each, some Lithium in the BOB's and a bunch of Alkalines (I get those 30 packs for $10 from HomeDepot too). I try to rotate those, when I buy a new pack I open it and swap the battereis from the BOB with those in the pack so the newest are always stored,
I've also tried to standardize as much as possible on AA's. I still have a little bit of gear that uses AAA's like a small radio and ARC AAA and minimag AAA's but am trying to stick with AA's for new purchases.
I'm going back down the rechargeable road now too. I have used NiMH in the past but the self discharge was terrible. Tried the renewal rechargeable alkailines and they worked well but long term sotrage they tended to leak if not topped off so I still had to maintain them like NiMH and it was hard to find a good charger. I still have a bunch of those now that my last charger has died. Added a radio which has a battery pack designed for AA NiCads. At the moment I'm testing it with NiMH's by pulling them out and charging but thats kind of a pain so I can't decide weather to buy NiCad's or try to convert it to run from a 9.6V NiMH pack charger by pulling out the NiCad charging circuitry from the packs. If I do that then I could standardize on just one type of rechargable.