Here are some quick links to the Blockchain white papers (marketing materials in some cases!) of some popular cryptocurrencies (altcoins) and cryptoassets(tokens). Hope reading these papers help you cut through the ICO marketing fog and understand the underlying technological merits and demerits.
Last updated : 16-June-2017
ethereum - ETH
bitcoin - BTC
ripple - XRP
zcash - ZEC
bitshares - BTS
dash - DASH
nxt - NXT
stratis - STRAT
nem - XEM
siacoin - SC
factom - FCT
stellar - STR
golem - GNT
monero - XMR
lisk - LSK
syscoin - SYS
steem - STEEM
augur - REP
cryptonite - XCN
bat - BAT
blackcoin - BLK
creditbit - CRB
zcoin - XZC
maidsafecoin - MAID
primecoin - XPM
gridcoin - GRC
reddcoin - RDD
peercoin - PPC
bytecoin - BCN
gnosis - GNO
decred - DCR
aragon - ANT
iconomi - ICN
antshares - ANS
emercoin - EMC