Sharing a wallet with a friend How can I share my bitcoin wallet with my family members? Such that if my grandmother spends one btc one day, I see that reflected on my computer, etc.

This is also a great safety mechanism, in case one of our family member's hard drive crashes, the other members will still have the wallet.
If you're looking for something technically straight-forward, I suggest using an "e-wallet" and giving your partner access to the wallet account.

Review these links:
https://en.bitcoin.it/wiki/Browser-based_wallet

And here are several e-wallet's listed:
https://en.bitcoin.it/wiki/Category:EWallets