Another protection type which I'm sure you'll be all to familiar with is the time-trial or 30 days protection. Sadly, most software authors implement their protection after they've spent considerable time on the full version, the concept of producing a specific trial version that permanently disables itself or prevents re-installation / BIOS cheating continues to elude them. Of course very little time-protected software is actually worth using past its evaluation period anyhow.
Sourcing time-trialled software is usually a pretty simple task. Magazine cover CD's bought at "kilo" prices are usually jam packed with suitable targets (although less so today than a few years back). Just flicking through one of my magazines (PC Direct November 1999), I've got some rather enticing Omniquad applications, PictureWorks HotShots (discontinued) & WinDelete 5 all for around £1.20 ($1.75 if you are American), these are good places to start your trials - and you'll probably be able to enjoy some worthwhile software in the process.
CompareFileTime, GetLocalTime, GetSystemTime, GetTimeZoneInformation, msvcrt.diffTime(), msvcrt.Time().
|123 ZIP! v2.0 & DropConvert v2.2||Cracking limited time runs with W32Dasm and your HEX editor.||June 1998|
|Borland C++ Builder v4.0||InstallShield and time-trial removing courtesy of +Tsehp.||17/01/00|
|CuteFTP v2.6 & HEdit v2.1.14||Elementary time-trial reversing by Sixx.||14/11/98|
|Extensis PhotoFrame v1.0||Following a serial number scheme to beat the 30 days.||30/12/98|
|FileNotes v3.2||Elegantly patching a 45 day trial and nag strings.||19/08/98|
|Fortres 101 v4.0||InstallShield PFTW password cracking and time-trial function exports.||11/01/99|
|HexDecOctBin Conv. v1.0||Kro_baR's first tutorial, nag and time-trial removing.||07/02/00|
|HVS ColorGIF v2.008||Lots of flags in this time trial and crippled plug-in.||29/12/98|
|HyperChem v5.02||A fairly tough time-trial/run-time & license protection.||19/07/98|
|Paint Shop Pro v5.0||"Its in the registry" by Santa Clawz.||10/02/99|
|Personal Inventory 98||Time-trial and nag screen/string removing with Borland Resource Workshop.||05/12/98|
|Premia Codewright v5.1b||Beating a time-trial and changing the contents of the About Box.||29/07/98|
|Revelation ViP Designer v2.5||Flag setting and 1Eh in another 30-day trial.||10/10/98|
|Ulead PhotoImpact v4.2||Simple time-trial and nag busting by Mr WhiTe.||30/07/99|
|Virtus OpenSpace 3D Author||Profiling a time-trial scheme before reversing it.||20/05/99|