There are a few other places where cache works:
1. It can help set up a Hunting Party deck - silver, cache, copper, and a terminal silver works almost as well as gold; in slow games (e.g. militia) it can be better to get to an 8 coin combo sooner than buy another HP and wait to get your gold.
2. It can work okay with counting house. One that works surprisingly well is cache/counting house in a colony game. You can buy counting houses at the end of the shuffle, particularly cards that will miss the shuffle (like a typical turn 5 purchase) and caches early in the shuffle. This provides more juice for the counting house and a gold to work with as well. It still gets beat hard by a lot of other options, but can get better with any sort of sifting (discarding coppers for benefit becomes much more powerful).
3. Draw/bank also works well with cache. Something like margrave or council room doesn't mind the bloat and having more treasures helps the bank a good bit.
4. Strong trashing. Say you open cache/chapel. The cache requires that you burn another turn or two on trashing, but increases your buying power very quickly (particularly if you have a second shuffle collision of your buys) and decrease the odds of having a sub-silver turn. Likewise, if you build a strong draw engine (e.g. border village/embassy), you can often chapel away the coppers in one go.
5. Cache is good starter food a pricey golem deck. Normally you want to buy your actions at 5 in a golem deck, but if your actions are above the 6 coin price point (e.g. goons/BV/expand/forge), or you are going to run into colliding terminals (too many council rooms early is not that great) then cache can help boot strap up to the expensive stuff. Cache works especially well with golem/sifters.
