Natmin is running a Telegram and Twitter Bounty giving away of $3000 eq. NAT each week - from now until the end of their token sale 31st December 2018 (NYE).
Also the Natmin ICO has uniquely participated in a number of strategic token swaps (i.e 1:1) and is running a co-sale with Contractium, where when you buy NAT tokens, you receive the equivalent ETH amount in Contractium tokens (CTU) - and vice versa.
Anyone can participate in the token sale, (USA included), because NAT tokens can be bought via exchanges - BitMart, TokenJar, YitBit and IQFinex.
It's a solid project that I'm really excited about. They've got a lot going on, you can see all updates and progress on the Natmin Pure Escrow Medium Blog here: https://medium.com/natmin-pure-escrow or check out the website to see what the project is all about (Natmin.io).