In our current campaign, I've hit upon a convenient house rule for the identification of magical items found in treasure. I know that a purist would demand that players use trial-and-error to figure out what every potion, wand, and suit of magical armor does -- or use magic/pay a magic-user to tell them. On the other hand, my group has limited real-world windows for play-time, and I'm not really keen on spending those few hours playing "drink the potion and see whether it levitates you or kills you."
I used to 'solve' this problem by just telling the players what they'd found, and how it worked.
This saves a lot of time, but it also means certain magic items just don't work - namely, cursed magic items, or even magic items with some unusual wrinkle or hidden cost of use! [Or, uh, I could just lie to my players, which I don't want to do].
But recently I hit upon a compromise solution that I've started using, and am pretty happy about. I don't know whether others have used it, but I'll share it here in hopes it helps someone else.
GUNDOBAD'S SNEAKY DICEY MAGIC IDENTIFICATION HOUSE RULE:
When the players recover a new magical item, I roll a d6, where the players can't see it.
+ If the die shows 2-6, I tell them exactly what the item is and does.
+ If the die shows a 1, I tell them they can't figure out what the item is, and they'll have to hunt someone down who can tell them - or experiment.
+ If the item is cursed or harmful...I roll the d6 anyway, but regardless of its result, I tell the players they can't figure out what the item is.
I'm not misleading the players; I've told them explicitly how the rule works. They know that in the rare cases that I won't identify a found magic item, it means either that it's cursed, OR they got a 1 on the 'identification' dice roll, and it's not cursed but something potentially quite useful.
In play, this means that the players can decide when something is worth experimentation, but it becomes an unusual and interesting quandary, not a recurring grindy drag.
So far, this rule has led to one cursed item that I refused to describe; there were enough contextual factors around it that the players fortuitously decided to destroy the item instead of trying to use it. Then, in our most recent session, they found a useful magic item but I rolled a 1, so now they've got an amulet pendant of unknown properties (a player tried it on, and nothing happened, so they'll have to try something else to see what this thing does...like go pay a sage to identify it).
Meanwhile, we can get on with the business of looting dungeons, without nerfing cursed or poisoned items. Yay!