Quandl has some dataset of altcoins but the history is small and unfortunately prices are not updated.
CoinMarketCap JSON API is great but I understand it provides the lastest update only.
I have found on Bitcoincharts a file named rippleUSD.csv.gz but I don't understand the structure. A convertion of the unixtime with in MS Excel (i.e. =A1/(60*60*24)+"1/1/1970") returns the following dates and time but it is not clear if the last column is price because movements in a single minute interval are huge.
Looking at the Market Overiew API I haven't found relative informations about CSV file structure. Sorry my status does not allow me to post more than 2 links
1362466270 5/3/13 6:51 AM 37.5 4.24384928
1362466300 5/3/13 6:51 AM 37.5 2.83321826
1362466300 5/3/13 6:51 AM 37.5 1.89147286
1362466330 5/3/13 6:52 AM 37.5 1.26275819
1362466330 5/3/13 6:52 AM 37.5 0.84302465
1362466340 5/3/13 6:52 AM 37.5 0.56264942
1362466340 5/3/13 6:52 AM 37.5 0.37568073
1362466350 5/3/13 6:52 AM 37.5 0.25084183
1362466350 5/3/13 6:52 AM 37.5 0.16748696
1362466380 5/3/13 6:53 AM 37.5 0.1118625
1362466380 5/3/13 6:53 AM 37.5 0.07468005
1362466410 5/3/13 6:53 AM 37.5 0.04984277
1362466410 5/3/13 6:53 AM 37.5 0.03327999
1362466480 5/3/13 6:54 AM 37.5 0.02228444
1362466490 5/3/13 6:54 AM 37.5 0.01485818
1362466490 5/3/13 6:54 AM 37.49999999 0.00990671
1362466520 5/3/13 6:55 AM 37.5 0.00660531
1362466520 5/3/13 6:55 AM 37.5 0.0044041
1362466550 5/3/13 6:55 AM 37.49999999 0.00293643
1362466790 5/3/13 6:59 AM 37.5 0.02613439
1362466930 5/3/13 7:02 AM 37.5 0.00194289
1362466980 5/3/13 7:03 AM 37.49999999 0.00130038
1362466980 5/3/13 7:03 AM 37.5 0.00087034
1362466990 5/3/13 7:03 AM 37.49999999 0.00058252
1362467000 5/3/13 7:03 AM 37.5 0.00038988
1362467000 5/3/13 7:03 AM 37.49999999 0.00026095
1362467030 5/3/13 7:03 AM 37.49999999 0.00011689
1362467030 5/3/13 7:03 AM 37.5 0.00017465
1362489380 5/3/13 1:16 PM 40.5 0.00014684
1362576360 6/3/13 1:26 PM 45 3.63539587
1362577870 6/3/13 1:51 PM 44.99999999 4.06298514
1362578760 6/3/13 2:06 PM 44.99999999 1.55555555
1362578950 6/3/13 2:09 PM 45 0.74606342
1362604140 6/3/13 9:09 PM 45.4 4.24261608
1362617400 7/3/13 12:50 AM 44 3.99999999
Do you know if there is website where it is possible to download historical price of big cap crypto currencies such as Dogecoin, Bitshares, DarkCoin and Ripple ?
Thank you,