(moving this to the Rules and Policies category as there is no OAuth implementation question here)
It sounds like your reason for asking this is that you want to create multiple applications in order to circumvent the rate limits?
Per the Developer Agreement:
Rate Limits. You will not attempt to exceed or circumvent limitations on access, calls and use of the Twitter API (“Rate Limits”), or otherwise use the Twitter API in a manner that exceeds reasonable request volume, constitutes excessive or abusive usage, or otherwise fails to comply or is inconsistent with any part of this Agreement.
In the Developer Policy:
Do not do any of the following:
Use a single application API key for multiple use cases or multiple application API keys for the same use case.
This includes using multiple applications in the way you are describing. You can have many applications with a single account, but the expectation is that the keys and tokens for each would be used for different purposes, and not used to “multiply” rate limits.
If you would like to track more users of keywords against a streaming API, then you should consider one of the Gnip APIs such as PowerTrack (these are commercial products).