How about tipping users on Stack Exchange sites?
67449
Offering actual money as a bounty?
144213
Set data tips programmatically?
69448
Posting to share knowledge instead of a strict Q&A
117767
Put bounties on other people's questions?
101632
Change misleading tooltip for feature request questions
81670
Proposing Windows as its own Stack Exchange site?
142137
Is there any app for Stack Exchange?
155702
Calculating the tipping point of a lamp post
23614
A method for the OP to accept comments?
52653
How can I PM people on this site?
131911
High rep users suggesting edits to authors
101134
Bonus Reputations for starters, new users
19435
Can I use the Stack Exchange concept in my own sites?
119457
Would it be better to encourage people to set a user name?
70079
Notify users about edit suggestion on their own posts
79632
How to tip housekeeping in hotels if leaving tips daily?
64345
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