[olegkikin]

> I use the keyconv program from vanitygen as a convenient way to do this. Simply running "keyconv -G" generates an address and private key and outputs them.

You have to really trust that vanitygen tool. If there's some bug where there's not enough entropy in the private key generation, ALL your temporary wallets become vulnerable (e.g. someone can generate your private keys).

[jstanley]

The keyconv program is extremely short, it simply calls the key generation routines in OpenSSL.