I have made a list of still active and very promising projects for the end of February and March 2018. There are many Airdrops and Free Coin Giveaways on the Internet, many of them are just scams or not giving huge value or potential. That's why I selected the most promising ones' at the moment. If you see any other interesting projects, which I have missed here just feel free to comment and ask.

Viberate (VIB)

A very promising coin from music sharing sector. Already listed on many exchanges like Bittrex. You can withdraw the coins and exchange them immedietely! You get 50 VIB for registration and many more for participating in refferal and promotion programs.
https://www.viberate.com/referrals/0c5320dd_0ef82bcc_c8cba581

Cappasity (CAPP)

Already listed on exchanges like Kucoin and Cryptopia. You get 5 CAPP for registration and additional 10 per refferal.
https://t.me/CappasityAffiliateBot?start=YXV0aDB8NWE4ZmQ4YTQxYTZmMWU3MjBhZTY0NmNm

Aelf (ELF)

Get Aelf coins for free. Already listed on main exchanges line Binance and ranked 65th on CoinMarketCap! You earn coins by registration, refferals and completing some quick tasks on their site. You can withdraw ELF to an exchange or just keep for a long time.
https://candy.aelf.io/account/register?invitationCode=0F1MbE0ZfL7K

SynapseAI

A future competitor of DeepBrainChain and SingularityNET Artificial Inteligence projects. You get 50 SYN for registration and 100 per each refferal.
https://tokensale.synapse.ai/r/13642

YourBlock (YBK)

YourBlock is an extremely promising new ICO with highly professional and experienced dev team. It is a stricktly private and personal data storage platform. You can get 20 YBK for joining the Telegram Group and additional 10 per each refferal.
https://t.me/yourblock_bot?start=CdbJDXPkpBxdKoRGUbVjpY

WCX

WCX is the new Global Low-Cost Digital Currency Exchange. Extremly interesting project with huge potential. You can get 50 WCX per registration plus 50 per each person you will reffer.
https://ico.wcex.co/?ref=MHNS68eC

Sphere

A great project with very experienced and professional team. One of the best ICOs of 2018. You get 50 Sphere coins for registration and 50 per refferal.
https://sphere.social/?ref_code=6wxph53vrgnb

CORBIT

A professional decentralized exchange with extremely promicing ICO. Get 30 Corbit tokens for free and 10 per each person you reffer.
https://corbit.website/airdrop/4JC6d

Viuly (VIU)

A decentralized video sharing platform already listed on EtherDelta and Bit-Z exchanges. You get 10 VIU for registration and many more for refferal and video watching.
https://viuly.io/r/K7424175a89d6f5a

Energy Token

Interesting energy project with huge persperctives. Get 100 coins for registration and additional 50 for every refferal.
http://tokenenergy.net/?invite=2779

NAUTICUS

New ICO of Nauticus Blockchain. Right now you can get 100 tokens for registration and additional 100 per each person you reffer. High future potential!
https://nauticus.io/ref/ec0ef379200487a1e190510429e31522248f5cc0e8a957e9cf32d2d025df7390

MaxData

New ICO Airdrop of MaxData project. Professional team, very interesting idea and many free coins for both registration and refferals.
https://airdrop.maxdata.io/?kid=MABCF

Phoenix (PHNX)

Coin already listed on exchanges like Cryptopia. You can exchange it or just use as a long-term investment. You get 300 PHNX for registration and additional 100 per each refferal.
https://phnxtoken.com/?r=30612