user10483: Is it possible to make a wallet for BTC and store LTC and NMC or other coins in it?

user9505: I'm not sure if there is a software wallet to do this, but if you want it for cold storage, you can definitely create addresses for almost all the cryptocurrencies from a raw 256 bit private key. This allows you to just securely store the 256 bit key rather than the individual wallet files for multiple cryptocoins.
You can do this by:

Creating a 256 private key of 64 hex (0-9,A-F) digits
Open brainwallet.org and go to the "Generator" tab and select "secret exponent"
Paste your 64 hex digits into the "Secret Exponent" text box.
Select the coin type in the top right corner and the coins private key and address will be shown in the "Private Key" and "Address" areas.

As an example, the 256 bit private key A5F308EB5553464AD377C68D16CDB85F3C8D63CABAC8017BE6D9D9A43F7F0CDF is the following addresses:

BTC (Private): 5K5NXzAa7PE5irZFc9Va6eAN4zPfd2E9MBcrt1ea8j225ix6wpC
BTC (Address): 18S5Czkk3pp8vSwVsS8fD28HLxea6JcVc
LTC (Private): 6vP717i71ogxCET77yHXt2wY2Tx8ppgB7s22bCfbrBLdmZvbD5f
LTC (Address): LKMPLRJapi4sPj96g1RRwE5tVZKviuvMxS
NMC (Private): 74A5i3WERWPrjWmvkHmXhKLdgvR1Re3gGRJTZoRBpoNBk1JL8RM
NMC (Address): MvhoGrVjfRvNfThSmgkhsjB31aMhYnd5qs

Note that this is somewhat insecure as if someone knows the coin private key for one of the addresses, they can directly convert the coin private key back to the raw private key.
Also if you import a private key into a wallet program (eg: bitcoind), be aware that they may send change to new addresses.

user-1: Coinomi Universal HD Wallet will do exactly what you're looking for. 
Coinomi is a very secure and lightweight, universal, open-source HD wallet for Bitcoin and many altcoins. At the moment the supported coins are:

Bitcoin
Dogecoin
Litecoin
Peercoin
Darkcoin
Reddcoin
NuBits
NuShares
Blackcoin
Feathercoin
Rubycoin
Digitalcoin
Cannacoin

with more integrations on the way.

10483: <p>Is it possible to make a wallet for BTC and store LTC and NMC or other coins in it?</p>
 9505: <p>I'm not sure if there is a software wallet to do this, but if you want it for cold storage, you can definitely create addresses for almost all the cryptocurrencies from a raw 256 bit private key. This allows you to just securely store the 256 bit key rather than the individual wallet files for multiple cryptocoins.</p>

<p>You can do this by:</p>

<ol>
<li>Creating a 256 private key of 64 hex (0-9,A-F) digits</li>
<li>Open brainwallet.org and go to the "Generator" tab and select "secret exponent"</li>
<li>Paste your 64 hex digits into the "Secret Exponent" text box.</li>
<li>Select the coin type in the top right corner and the coins private key and address will be shown in the "Private Key" and "Address" areas.</li>
</ol>

<p>As an example, the 256 bit private key A5F308EB5553464AD377C68D16CDB85F3C8D63CABAC8017BE6D9D9A43F7F0CDF is the following addresses:</p>

<ul>
<li>BTC (Private): 5K5NXzAa7PE5irZFc9Va6eAN4zPfd2E9MBcrt1ea8j225ix6wpC</li>
<li>BTC (Address): 18S5Czkk3pp8vSwVsS8fD28HLxea6JcVc</li>
<li>LTC (Private): 6vP717i71ogxCET77yHXt2wY2Tx8ppgB7s22bCfbrBLdmZvbD5f</li>
<li>LTC (Address): LKMPLRJapi4sPj96g1RRwE5tVZKviuvMxS</li>
<li>NMC (Private): 74A5i3WERWPrjWmvkHmXhKLdgvR1Re3gGRJTZoRBpoNBk1JL8RM</li>
<li>NMC (Address): MvhoGrVjfRvNfThSmgkhsjB31aMhYnd5qs</li>
</ul>

<p>Note that this is somewhat insecure as if someone knows the coin private key for one of the addresses, they can directly convert the coin private key back to the raw private key.</p>

<p>Also if you import a private key into a wallet program (eg: bitcoind), be aware that they may send change to new addresses.</p>
 -1: <p><a href="http://coinomi.com/" rel="noreferrer"><strong>Coinomi Universal HD Wallet</strong></a> will do exactly what you're looking for. </p>

<p><a href="http://coinomi.com/" rel="noreferrer"><strong>Coinomi</strong></a> is a very secure and lightweight, universal, open-source HD wallet for Bitcoin and many altcoins. At the moment the supported coins are:</p>

<ul>
<li>Bitcoin</li>
<li>Dogecoin</li>
<li>Litecoin</li>
<li>Peercoin</li>
<li>Darkcoin</li>
<li>Reddcoin</li>
<li>NuBits</li>
<li>NuShares</li>
<li>Blackcoin</li>
<li>Feathercoin</li>
<li>Rubycoin</li>
<li>Digitalcoin</li>
<li>Cannacoin</li>
</ul>

<p>with more integrations on the way.</p>
