“ On a location with numerous webs, and at least one big spider, there is a something inside a cocoon. It is humanoid in shape, still moving. If the heroes free it (not before they kill or drive away the spiders), they meet a ... zombie!
The poor zombie wandered the dungeon alone, and tried to kill a big living creature (= a spider). The spider used the usual treatment, even if this victim did not look tasty. The zombie can be easily killed as any other zombie. It got but several doses of spider-poison, so can be something worth if it is extracted. You can mention to a druid or ranger the fact the spider had no poison anymore.”
“ As the PCs travel the road, right after a bend they hear a sharp whistle and call: 'Heeey, not so lazy, move your asses!' It is a large man that calls, and there are unwilling workers that listen. A small company, 10-15 men work on the road, push boulders aside, dig up roots from under the road, etc. The large man that shouted turns to you, smiles fast and mutters something under his breath, sounds like cursing some lazy worker. 'Where does the road bring you from, travellers?' And does a little small-talk.
And what is really happening? A group of bandits is 'adapting' the road for shady purposes. The road will not be wider, but tighter, with enough cover around (and a few traps perhaps), and will become an ideal spot for ambushing travellers or entire caravans. The bandit leader wants them all to appear harmless. The 'lazy worker' he cursed was actually a guard that should give warning before any travellers come around (fallen asleep). Not surprisingly, the boss may decide for an ambush even now.”