Par exemple sur les machines à sous, des free spins sont souvent offerts.
https://talkingpoints.org/subx/showthread.php?tid=22154
https://taiyule.com/forum.php?mod=viewthread&tid=6219&extra=
https://www.clubhombre.com/mybb/showthread.php?tid=16750
http://www.lada-xray.net/showthread.php?p=154279#post154279
http://forum.spolokmedikovke.sk/viewtopic.php?f=18&t=827441
http://qrfonline.qrfmag.com/qrfswap/viewtopic.php?t=75092
http://strada.bielsko.pl/1_lubelskie/forum/4-zadaj-pytanie/543138-big-bass-amazon-xtreme-la-machine-a-sous-preferee-pour-gagner-gros#543138
http://forum.spolokmedikovke.sk/viewtopic.php?f=4&t=971864
http://forum.spolokmedikovke.sk/viewtopic.php?f=8&t=997568
http://www.prepody.ru/topic54330.html
http://www.prepody.ru/topic45132.html
