Barring quests and badges (which aren't repeatable, so can't be farmed), the only way I know to gain favor with a Giant is by donating at shrines. I'm currently churning out Sammiches as fast as I can and dumping them into Lem's shrines so that I can unlock Better Learning III, but it's slow going.
Is there a more efficient way to gain favor? The wiki page is fairly thin. If nothing else, are there crafting recipes which offer a better favor/energy ratio?
Best Answer
Since favor gained is related to the value of the item donated, you'll want to find high value items that are relatively easy to get. What items you use depends on your current skill set.
Many people swear by sparkly rock, which you can mine efficiently with Mining level 3 or 4. You also gain gems this way, which can be extraordinarily valuable.
If you have high Animal Kinship, it is extremely profitable to gather meat and donate that directly. Finding streets or zones with many pigs at the highest AK level can easily fill your bags with delicious and profitable meat.
Most recipes for items can't beat the cost/benefit ratio of those raw materials. If you want to craft things for donation, I think the best method is to sell your items in auctions and then use the currants to fund acquisition of items (ie, shrine powder, plus other auction house items that generally sell for less than they're worth).
If you're interested in maximizing your shrine donations, check out Zu's thread:
http://www.glitch.com/forum/general/9667/
...which is probably the authoritative source on all things shrine related.
I'll also pimp my FavorSaver tool:
http://agent86ix.github.com/glitch/