Try searching these scripts. I personally have used a few which have most of the requirements you have said. I have alot of idler purpose scripts which I have download over the years, so there not hard to find.
[1] Download MC_8's On 'Idle tcl'. (MC_8's website)
It has alot of features you can customize it.
[2] Download 'Idle King' another tcl showing the top channel idlers.
Just goto
www.egghelp.org/tcl.htm or
www.tclscript.com and search with the keyword 'idle'.
If you want more scripts ftp.eggheads.org, go into their tcl archive folder on the ftp, you will have scripts sorted from 1996 onwards upto today, with their corresponding eggdrop versions. (normally the old ones work on the new eggies too!)
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You can make one yourself to.
One way: Just make the bot do a foreach loop of [chanlist $chan] by a continuous timer say every 1 min or you can bind that to join, part or etc. Then get the users idle times by 'getchanidle <nickname> <channel>', compare them with a defined value if they are greater than your defined value, go ahead and reward them, supponsingly a voice maybe or something like that.
