It might help if you could post a little more information about what you need the database for and what your level of computer expertise is (e.g. are you familiar with Unix?). A ‘lighter’ version of FileMaker Pro exists under the name ‘Bento’. This is a much simplified version of FileMaker but still very powerful and useful for many basic needs. If you are familiar with Unix/Linux then sqlite is a free and relatively simple SQL database which is widely used.
Without more information from you it is impossible to recommend a database. The advantages/disadvantages of any one choice will largely concern cost, your level of expertise with databases/Unix/programming, the demands you have from any software, your choice of OS etc.
In our lab, we mainly need the database for putting together a database of reagents and clones and kits etc that have been recently bought by other members of the lab.
This is to help those who needs such things in a mighty hurry but cannot get delivery in time for experiments. So this is the main purpose.
And about computer knowledge, I dont have any idea about SQL or Linux.
Your needs seem relatively simple (especially compared to the complexities of some database software). If you use Macs I would suggest something very simple like Bento. I don’t know what the equivalent would be on a PC. But a full-blown database might be overkill for you.
Filemaker is also Mac only (unless they changed it).
If it is just to manage big lists & spreadsheets, you probably can get away with MS Excel/Access or OpenOffice Calc/Base on one regularly backed up computer. Or some google-docs / MS Live cloud-based spreadsheet thing.
You should be aware that some database programs save any changes immediately and automatically (i.e., don’t require a save command), so it’s very easy to inadvertently delete an entry. You may want to restrict users’ ability to modify the database (e.g., allow entries but not deletions/edits).
I would also add, that there are probably various websites that could be retooled to suit your purposes. E.g. you could have information in a shared spreadsheet using Google Docs. I would imagine that there must be some websites that offer databases as well.