Mobile clients like BeeJive and Meebo do that, simply because they can't keep a connection open on the client 24/7. I don't know of any native desktop clients that do it because it's usually not needed, but programs like bitlbee can run on a server and proxy to all of your accounts, which you then read with one IRC client once you connect.
The feature of Google Talk that queues messages is natively supported by most Jabber/XMPP servers, though, where the server can queue up messages for clients while they are disconnected.
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Mobile clients like BeeJive and Meebo do that, simply because they can't keep a connection open on the client 24/7. I don't know of any native desktop clients that do it because it's usually not needed, but programs like bitlbee can run on a server and proxy to all of your accounts, which you then read with one IRC client once you connect.
The feature of Google Talk that queues messages is natively supported by most Jabber/XMPP servers, though, where the server can queue up messages for clients while they are disconnected.