Just brought this up in another thread....a thought to somehow get some mileage out of the Ecclesitheurge....
A scribe scroll based Ecclesitheurge build.....
Most cleric deities have 4-5 domains and 4-5 subdomains - with the associated differing domain spells and the ECC can rotate through these.
Now if you got your UMD up to a good level (traits, feats, CHA, equipment, skill ranks), you could go through these fairly easily scribing scrolls as you went, giving you a good increase in the spells available to you.
Yes you have a DC 20 + CL to pass but its extremely do-able, especially considering you get a further +2 on your check if you have attempted it with the same item before.
You can potentially make it less of a burden feat/trait wise by making one of your domains always Glory (to get the CHA bonus) but this means restricting your deity choice or going cleric of a concept.
All going well you can also start talking to wizards and druids to start scribing even more scrolls with useful spells....
Very niche.... but potentially quite useful.....
Any thoughts on good domain/subdomain combos to get the most number of non-cleric spells?
Craft Wand seems easier on the UMD and more efficient with cost, if this is to be a cornerstone of the character. Maybe even Craft Staff if the character starts at a late enough level.
Domains, hmm. Fire/Smoke is good, as is Earth/Caves or most varieties of Void. Water/Flotsam has a granted power which would synergise with your intent best though I think, and it comes with deities which don't overlap these that I know of. A quick search brings up Jubilex (ick, especially if you've read the original AD&D 1e description), a goblin goddess, and an empyreal lord I've never heard of before.