I discovered this opportunity very late, but if you hurry you can beat the deadline of May 10th, 2021.
GlocalMe is offering 100 free miles to every Turkish Airlines Miles & Smiles member who “signs up”. However this requires nothing more than an email address:
The 100 miles should reach your account within 30 days.
I don’t know whether I will ever need to pay for a portable wifi service from Glocal, but I’m happy to hand over a junk email address in exchange for 100 free miles… 🙂